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The difference between stainless steel and carbon steel

Stainless steel differs from carbon steel by the amount of chromium present. Unprotected carbon steel rusts readily when exposed to air and moisture. This iron oxide film (the rust) is active and accelerates corrosion by making it easier for more iron oxide to form. Since iron oxide has lower density than steel, the film expands and tends to flake and fall away.  In comparison, stainless steels contain sufficient chromium to undergo passivation, forming an inert film of chromium oxide on the surface. This layer prevents further corrosion by blocking oxygen diffusion to the steel surface and stops corrosion from spreading into the bulk of the metal. Passivation occurs only if the proportion of chromium is high enough and oxygen is present.

𝐖𝐡𝐚𝐭 𝐌𝐚𝐤𝐞𝐬 𝐒𝐭𝐚𝐢𝐧𝐥𝐞𝐬𝐬 𝐒𝐭𝐞𝐞𝐥 𝐌𝐚𝐠𝐧𝐞𝐭𝐢𝐜?

𝐖𝐡𝐚𝐭 𝐌𝐚𝐤𝐞𝐬 𝐒𝐭𝐚𝐢𝐧𝐥𝐞𝐬𝐬 𝐒𝐭𝐞𝐞𝐥 𝐌𝐚𝐠𝐧𝐞𝐭𝐢𝐜? For stainless steel to be magnetic, it must contain iron in its chemical composition. That takes care of the first requirement.The second requirement is that the stainless steel must have its crystal structure be arranged in a ferrite or martensite structure.If stainless steel is mostly comprised of an austenite structure, then it will not be magnetic.Most stainless steels falling under this category are non-magnetic because they contain high amounts of austenite.Even though some of the metals like grade 304 and 316 have iron in their chemical composition, they are austenite, meaning they are non-ferromagnetic.

What's the application of nickel

What's the application of nickel?  Nickel is primarily sold for first use as refined metal (cathode, powder, briquet, etc.) or ferronickel.   About 65% of the nickel consumed in the Western World is used to make austenitic stainless steel.  Another 12% goes into superalloys (e.g., Inconel 600) or nonferrous alloys (e.g., cupronickel).  Both families of alloys are widely used because of their corrosion resistance.   The aerospace industry is a leading consumer of nickel-base superalloys.  Turbine blades, discs and other critical parts of jet engines are fabricated from superalloys.  Nickel-base superalloys are also used in land-based combustion turbines, such those found at electric power generation stations.  The remaining 23% of consumption is divided between alloy steels, rechargeable batteries, catalysts and other chemicals, coinage, foundry products, and plating.  Title

how does stainless steel improve modern day life?

how does stainless steel improve modern day life?Stainless steel has many environmental and social benefits. Stainless steel products enable us to lead a healthier life and are cleaner for the environment as well. Even though it is impossible to demonstrate all areas where it is beneficial, below are some of the main examples where stainless steel is used.Improvements to air qualityAir emissions are always a problem in today’s moving world, where pollution is of such high importance. The greater influx of cars on the road, planes in the air and production factories all add to the problem. The effect of increased levels of ‘greenhouse gases’ on climate change is maybe the most debated example although pollutants which cause ‘acid rain’ are also worth noting. Ways in which stainless can help reduce this problem can be: New catalytic converters use stainless steel for the holding and transportation of catalytic substances. The newest versions are much lighter and stronger than traditional ceramic versions as well as being much more energy efficient. Catalytic substances are usually highly corrosive and are active within a high temperature environment, thus being the reason for stainless steel being the chosen material. These stainless steel converters help to decrease pollution on motor vehicles, generator sets, forklifts, mining equipment, trucks, buses and trains etc.  Reduction in the use of fossile fuels· Stainless steel can be used in the manufacture of condensing boilers. Condensing boilers are today’s most energy efficient heating method, with a 100% efficiency rating. Stainless steel is required because of the condensation that occurs during the process; therefore corrosion resistance is of high importance.· · Fuel cells are a source of energy for the future. Much like a battery the fuel cell converts chemical energy into electrical energy. Working from either natural gas or hydrogen, they generate heat and electricity with only one emission; water. Stainless steel is used for supporting the electrodes which are stronger, easier to manufacture and cheaper than ceramic versions. Fuel cells can be used in a variety of places including in cars and in domestic heating systems alike. · Keep water cleanIt is so important that water is kept clean, not just for our health but for the environment as well. Stainless steel can be used to improve the cleanliness of water. The list below shows how stainless steel can help keep water cleaner:· Stainless steel pipes for drinking systems help to keep water clean and quality standards high. Stainless steel guarantees lasting hygiene and prevents the formation of any medium on which bacteria can grow. Correct grade selection will minimise the risk of any localised corrosion, meaning there is practically no contamination of water in contact with the stainless steel. Leaching levels of nickel and chromium have also been proven to be less than the maxima permitted by the European Drinking Water Directive.For more information on stainless steels and drinking water · Waste water plants are using stainless steel in the transportation of waste water products, due to the possible corrosive nature of the water. Stainless steels durability and low maintenance also make it the best material to use. Therefore the reason for stainless steel is to maximise service life and to minimise malfunctioning. Reduces wasteStainless steel can be used to prevent the amount of waste gases and materials given off, as well as the disposal of waste products. The list below demonstrates some areas where waste reduction occurs:· Because the composting process releases many corrosive gases, stainless steel is best used for this process. Other reasons for its use include its ability to last over a long time period, therefore making it more economically attractive.· Stainless steel is being used for the recycling of cardboard and paper, meaning it makes a major contribution to the reduction of the waste steam as well as the protection to trees.·     This article orgin from Bristish Stainelss Steel Association:  https://bssa.org.uk/bssa_articles/environmental-aspects-of-stainless-steel/#top

The difference of hot rolling stainless steel and cold rolling stainless steel

Hot rolling is above the recrystallization temperature of rolling; Cold rolling is below the recrystallization temperature of rolling, both are based on the hot strip rolling. And then recover its mechanical properties by annealing . It generally under process such as hot rolling,acid pickling, cold rolling and annealing. There is no oxide coating during cold rolling process. In this way, the surface of the cold rolling stainless steel will be good and in high size precision. There will be oxide coating in hot rolling process. It will make the bad tolerance of stainless steel plate and not good in smoothness and toughness. And the price of hot rolling stainless steel product will be lower.

How to select the right stainless steel material for railing / ornamental application

Stainless steel 304# and 316# are the most popular types of stainless for railing systems. Railing systems made from each of these two types offer different strengths and weaknesses. Understanding your options and which applications are suited for each is essential when specifying a new steel railing.304-grade stainless is also known as “18-8 stainless,” referring to its composition of 18% chromium and 8% nickel. This type of stainless steel is often used in indoor applications. Finishes from satin (240 grit) to finer finishes, including mirror finish, are available. In addition to looking good, these finishes serve a practical purpose as well: satin finishes, for example, are easy to maintain while mirror finishes offer ultimate corrosion resistance.In addition to interior applications, 304-grade stainless also performs well in outdoor environments where conditions are not overly harsh or extreme, or where the railing system is protected from the environment.316-grade stainless tackles harsh environments with a slightly higher nickel content and two percent molybdenum to further strengthen its corrosion resistance. In turn, these added alloys make 316-grade the ideal choice for outdoor applications or where harsh environmental factors require a more durable material. As with 304-grade stainless, no protective coating is required and a variety of finishes are available to create the right look for any application.316-grade steel is the most popular choice for outdoor and industrial applications due to its proven performance in harsh conditions. While no material is completely impervious to corrosion, 316-grade stainless can withstand years of abuse if properly maintained. 

Recycling and reusing of stainless steel

Stainless steel is 100% recyclable. An average stainless steel object is composed of about 60% recycled material of which approximately 40% originates from end-of-life products and about 60% comes from manufacturing processes. According to the International Resource Panel's Metal Stocks in Society report, the per capita stock of stainless steel in use in society is 80–180 kg in more developed countries and 15 kg in less-developed countries.There is a secondary market that recycles usable scrap for many stainless steel markets. The product is mostly coil, sheet, and blanks. This material is purchased at a less-than-prime price and sold to commercial quality stampers and sheet metal houses. The material may have scratches, pits, and dents but is made to the current specifications.

What is your package

Packaging Inner Packaging Each Tube is packed by a plastic bag individually. Then a label will sticked on the plastic bag or on the tube. Outside Packaging Weaving Bag PackagingIt usually used for small bundles packaging Each bundle is about 20-30 kgs. Therefore, its normally required by the client who need manual handling for the goods. Hollow Plate Packaging Each bundle for this packaging is about 500Kgs. It usually required by the client who require for the mechanical handling of the goods. Wooden Box Packaging Wooden box is usually used for short tube packaing. And some client who have high requirements  to protect the goods during the delivery will also pack in this way. Steel box Packaging It usually used for LCL delivery. And some client who have high requirements  to protect the goods during the delivery will also pack in this way.

Care and maintenance of stainless steel

IntroductionStainless steels are selected for applications where their inherent corrosion resistance, strength and aesthetic appeal are required. However, dependent on the service conditions, stainless steels will stain and discolour due to surface deposits and so cannot be assumed to be completely maintenance-free. In order to achieve maximum corrosion resistance and aesthetic appeal, the surface of the stainless steel must be kept clean. Provided the grade of stainless steel and the surface finish are correctly selected, and cleaning schedules carried out on a regular basis, good performance and long service life will result.Factors affecting maintenanceSurface contamination and the formation of deposits on the surface of the stainless steel must be prevented. These deposits may be minute particles of iron or rust generated during construction. Industrial and even naturally occurring atmospheric conditions can produce deposits which can be equally corrosive, e.g. salt deposits from marine conditions.Working environments can also provide aggressive conditions such as heat and humidity in swimming pool buildings. These conditions can result in surface discolouration of stainless steels and so maintenance on a more frequent basis may be required.Modern processes use many cleaners, sterilizers and bleaches for hygienic purposes. Proprietary solutions, when used in accordance with makers' instructions, should be safe but if used incorrectly (e.g. warm or concentrated), may cause discolouration or corrosion on stainless steels. Strong acid solutions are sometimes used to clean masonry and tiling of buildings. These acids should never be used where contact with metals, including stainless steel, is possible. If this happens, the acid solution must be removed immediately, followed by dilution and rinsing with clean water.Maintenance programmeWith care taken during fabrication and installation, cleaning before 'hand-over' should not present any problems. More attention may be required if the installation period has been prolonged or hand-over delayed. Where surface contamination is suspected, immediate cleaning after site fixing should avoid problems later. Food handling, pharmaceutical, aerospace and certain nuclear applications may require extremely high levels of cleanliness applicable to each industry.The frequency of cleaning is dependent on the application - a simple rule is:Clean the metal when it is dirty in order to restore its original appearance.This may vary from once to four times a year for external applications, but may be daily for items in 'hygienic' applications. Recommendations on cleaning frequencies in architectural applications are shown below.Cleaning frequency in architectural applicationsLocation430 (1.4016)304 (1.4301)316 (1.4401)InternalAs required to maintain appearance or designSuburban or rural6-12 month intervals (as appropriate to location and design)Industrial or urbanGrade not recommended3-6 months6-12 monthsCoastal or marineGrade not recommendedGrade not recommended6-12 monthsThis article is excerpted from www.bssa.org.uk

What is Salt Spray Testing of Stainless Steel ?

Salt spray testing is an accepted method for assessing the suitability of stainless steel parts and fabrications that are likely to encounter chloride environments in service.For any particular part, tested under laboratory conditions, a difference in performance between say, 430 (1.4016), 304 (1.4301) and 316 (1.4401) types would be expected, but the test outcome is sensitive to the shape of the parts (designed-in crevices), surface finish and the test conditions.Using specific laboratory salt spray test data to assess if a particular steel grade is suitable for a specific or 'generic' environment is therefore not appropriate.Salt spray test methodsSalt spray testing is covered by the standards such asASTM B 117 - Practice for Operating Salt Spray (Fog) Testing ApparatusTests durations may be up to 260 hours.BS7479:1991 - Method for Salt Spray Corrosion Tests in Artificial AtmospheresThis supercedes BS5466:1977 and is equivalent to ISO 9227.This standard covers methods in three types of atmospheres: -NeutralAcetic acidCopper accelerated acetic acid (CASS)The test duration's range from 2 to 96 hours.The pass / fail criteria is that thers should not be any 'visible' staining on parts tested.The test acceptance criteria can therefore be subjective and need to be clearly defined for any set situation.Comparison of 316, 304 and 430 type stainless steels in salt spray testingResults from one testing laboratory, based on tests done to the ASTM B117 method suggest a 316 type part could be expected to pass a 96 hour test using a 3% salt spray.Indications are that longer test times would not be expected to give satisfactory results.In contrast, 304 type parts would not be expected to give satisfactory results in a 3% salt spray, but if the salt solution concentration is reduced to 0.3 %, then it is possible that a 304 type parts may be satisfactory for test times up to 120 hours.This could also apply to 430 type ferritic or 431 type martensitic stainless steel parts.All of the stainless steel tube for heat exchanger and sanitary tube from Vinmay are strictly inspected  by salt spray test methods. We ensure the inner side of our ASTM A249 / EN10217-7 and ASTM A270 /EN10357  tubes with corrosion and will meet the requirement of heat exchanger and sanitary industry. Welcome for enquiry. 

What types of Corrosion Can Occur in Stainless Steels?

The most common types of corrosion in stainless steel are:Pitting corrosion - The passive layer on stainless steel can be attacked by certain chemical species. The chloride ion Cl- is the most common of these and is found in everyday materials such as salt and bleach. Pitting corrosion is avoided by making sure that stainless steel does not come into prolonged contact with harmful chemicals or by choosing a grade of steel which is more resistant to attack. The pitting corrosion resistance can be assessed using the Pitting Resistance Equivalent Number calculated from the alloy content.Crevice corrosion- Stainless steel requires a supply of oxygen to make sure that the passive layer can form on the surface. In very tight crevices, it is not always possible for the oxygen to gain access to the stainless steel surface thereby causing it to be vulnerable to attack. Crevice corrosion is avoided by sealing crevices with a flexible sealant or by using a more corrosion resistant grade.General corrosion - Normally, stainless steel does not corrode uniformly as do ordinary carbon and alloy steels. However, with some chemicals, notably acids, the passive layer may be attacked uniformly depending on concentration and temperature and the metal loss is distributed over the entire surface of the steel. Hydrochloric acid and sulphuric acid  at some concentrations are particular aggressive towards stainless steel.Stress Corrosion cracking(SCC) - This is a relatively rare form of corrosion which requires a very specific combination of tensile stress, temperature and corrosive species, often the chloride ion, for it to occur. Typical applications where SCC can occur are hot water tanks and swimming pools.  Another form known as sulphide stress corrosion cracking (SSCC) is associated with hydrogen sulphide in oil and gas exploration and production.Intergranular corrosion- This is now quite a rare form of corrosion. If the Carbon level in the steel is too high, Chromium can combine with Carbon to form Chromium Carbide. This occurs at temperatures between about 450-850 deg C. This process is also called sensitisation and typically occurs during welding. The Chromium available to form the passive layer is effectively reduced and corrosion can occur. It is avoided by choosing a low carbon grade the so-called' L' grades or by using a steel with Titanium or Niobium which preferentially combines with Carbon.Galvanic corrosion - If two dissimilar metals are in contact with each other and with an electrolyte e.g. water or other solution, it is possible for a galvanic cell to be set up. This is rather like a battery and can accelerate corrosion of the less 'noble' metal. It can avoided by separating the metals with a non-metallic insulator such as rubber.         All of the tubes are made from first class material which produce by famous suppliers, such as BAOSTEEL, TISCO, TINGSHAN, etc, which can make sure the high stability and corrosion resistance. And the surface of the tubes are very well.In this way oru product are not easy to be rust

How many types of stainless steel are there?

Stainless steel is usually divided into 5 types:Ferritic – These steels are based on Chromium with small amounts of Carbon usually less than 0.10%. These steels have a similar microstructure to carbon and low alloy steels. They are usually limited in use to relatively thin sections due to lack of toughness in welds. However, where welding is not required they offer a wide range of applications. They cannot be hardened by heat treatment. High Chromium steels with additions of Molybdenum can be used in quite aggressive conditions such as sea water. Ferritic steels are also chosen for their resistance to stress corrosion cracking. They are not as formable as austenitic stainless steels. They are magnetic.Austenitic - These steels are the most common. Their microstructure is derived from the addition of Nickel, Manganese and Nitrogen. It is the same structure as occurs in ordinary steels at much higher temperatures. This structure gives these steels their characteristic combination of weldability and formability. Corrosion resistance can be enhanced by adding Chromium, Molybdenum and Nitrogen. They cannot be hardened by heat treatment but have the useful property of being able to be work hardened to high strength levels whilst retaining a useful level of ductility and toughness. Standard austenitic steels are vulnerable to stress corrosion cracking. Higher nickel austenitic steels have increased resistance to stress corrosion cracking. They are nominally non-magnetic but usually exhibit some magnetic response depending on the composition and the work hardening of the steel.Martensitic - These steels are similar to ferritic steels in being based on Chromium but have higher Carbon levels up as high as 1%. This allows them to be hardened and tempered much like carbon and low-alloy steels. They are used where high strength and moderate corrosion resistance is required. They are more common in long products than in sheet and plate form. They have generally low weldability and formability. They are magnetic.Duplex - These steels have a microstructure which is approximately 50% ferritic and 50% austenitic. This gives them a higher strength than either ferritic or austenitic steels. They are resistant to stress corrosion cracking. So called “lean duplex” steels are formulated to have comparable corrosion resistance to standard austenitic steels but with enhanced strength and resistance to stress corrosion cracking. “Superduplex” steels have enhanced strength and resistance to all forms of corrosion compared to standard austenitic steels. They are weldable but need care in selection of welding consumables and heat input. They have moderate formability. They are magnetic but not so much as the ferritic, martensitic and PH grades due to the 50% austenitic phase.Precipitation hardening (PH) - These steels can develop very high strength by adding elements such as Copper, Niobium and Aluminium to the steel. With a suitable “aging” heat treatment, very fine particles form in the matrix of the steel which imparts strength. These steels can be machined to quite intricate shapes requiring good tolerances before the final aging treatment as there is minimal distortion from the final treatment. This is in contrast to conventional hardening and tempering in martensitic steels where distortion is more of a problem. Corrosion resistance is comparable to standard austenitic steels like 1.4301 (304). 

Electropolishing of stainless steels

IntroductionMost stainless steel types and forms, ie wrought or cast, can be successfully electropolished. Electropolishing of sulphurised free-machining grades, however, does not give a high standard of surface finish.The anodic dissolution of a thin layer of the surface is similar in principal to electropolishing that can be done on other metals. Around 20 to 40 microns of the surface is removed, leaving a smoothed surface that optimises the corrosion resistance of the steel in any given environment.The electropolishing process for stainless steelsThe process uses relatively low voltages of between 12 and 18 volts, but with large currents of between 750 and 3000 amperes. This gives anode current densities around 20 to 40 amps/dm2 (amps per square decimetre). The stainless steel item that is being electropolished is the anode in this direct current cell. Electrolytes used are usually mixtures of phosphoric and sulphuric acids.The process takes around 10-20 minutes.The process induces preferential dissolution of the 'peaks' or high spots on the surface of the work piece. This results in a net smoothing of the surface, which is also beneficial in removing surface stresses left over from mechanical polishing pre-treatments. Contamination and debris left from mechanical surface treatments is also removed by electropolishing. However, scratches and visible surface irregularities are not likely to be removed by electropolishing. Non-metallic inclusions at the surface of the steel may also be more visible after electropolishing, compared to the finish after mechanical polishing methods. Electropolishing can be used on castings to check the surface soundness.The design of holding jigs is critical, especially on complex shapes, as it influences the consistency of the polished surface and reduces the risk of gas streaking. Both hydrogen and oxygen are generated as a bi-product of the process, with the oxygen coming from the stainless steel 'anode'. This means that there is no risk of any hydrogen embrittlement to the stainless steel from the electropolishing process. Benefits of electropolished finishes on stainless steel productsOptimisation of the corrosion resistance of finished stainless steel components. Micro-crevices on the surface are eliminated. Electropolished surfaces should be fully passive and no further passivation treatments are necessary.Can be used on complex shapes eg wire radiator grilles, where mechanical polishing is difficult or impossible.Improves surface reflectivity.Removes machining burrs on small components with a lower risk of entrapped surface contamination from prior mechanical polishing. This confers the added benefit of easier and more efficient in-service cleaning of electropolished items.Lower tendency for contact substances to adhere (cake-on) to component surfaces and for fibres to 'snag' in paper and textile processing applications.Improves surface cleansability compared to mechanically finished surfaces.Lower rate of bacterial growth in food industry applications.Lower surface stresses in machined components. Improved fatigue life has resulted where stainless steel springs have been electropolished, especially compared to normal shot peening treatments.Elimination of occluded surface gases from items operating under high vacuum conditions. Typical applicationsThere is a wide range of product and industry applications for electropolished stainless steel items.These include :-ArchitecturalGates, door furniture, floor (durbar) plating, handrails, lampposts, sculptures, glass panel fixings (wrought or cast) etc.AutomotiveRadiator grilles, bezels, bull-bars, safety equipment frames, tyre making plant vessels etcFood and BeveragesBrewing vessels, food mixing blades, vending machine water tanks, confectionery moulds etcLeisureSwimming pool building furniture such as ladders, and disabled lift framesMedicalSurgical implants, vein stents, surgical instrumentsPharmaceuticalProcess tanks, pipes and valves, powder hoppers etcPulp and paperScreen cylindersSemiconductor and high vacuum plantPipework, valves, pump parts, clean room process equipment and furnitureTextilesThis article is excerpted from https://www.bssa.org.uk/

What are the cleaning methods for stainless steel ?

Stainless steel is easy to clean. Washing with soap or mild detergent and warm water followed by a clear water rinse is usually quite adequate for domestic and architectural equipment. Where stainless steel has become extremely dirty with signs of surface discolouration (perhaps following periods of neglect, or misuse) alternative methods of cleaning can be used, as outlined below. RequirementSuggested Method CommentsRoutine cleaning of light soilingSoap, detergent or dilute (1%) ammonia solution in warm clean water. Apply with a clean sponge, soft cloth or soft-fibrebrush then rinse in clean water and drySatisfactory on most surfacesFingerprintsDetergent and warm water, alternatively, hydrocarbon solventProprietary spray-applied polishes available to clean and minimise remarkingOil and grease marksHydrocarbon solvents (methylated spirit, isopropyl alcohol or acetone) Alkaline formulations are also available with surfactant additions e.g.' Stubborn spots, stains and light discolouration. Water marking. Light rust stainingMild, non-scratching creams and polishes. Apply with soft cloth or soft sponge and rinse off residues with clean water and dry.Avoid cleaning pastes with abrasive additions3. Suitable cream cleansers are available with soft calcium carbonate additions, e.g. 'Jif', or with the addition of citric acid, e.g. Shiny Sinks1. Do not use chloride solutions8,9.Localised rust stains caused by carbon steel contaminationProprietary gels, or 10% phosphoric acid solution (followed by ammonia and water rinses), or oxalic acid solution (followed by water rinse).Small areas may be treated with a rubbing block comprising fine abrasive in a hard rubber or plastic filler. Carbon steel wool should not be used, nor should pads that have previously been used on carbon steel. A test should be carried out to ensure that the original surface finish is not damaged.Burnt on food or carbon depositsPre-soak in hot water with detergent or ammonia solution. Remove deposits with nylon brush and fine scouring powder if necessary. Repeat if necessary and finish with 'routine cleaning'.Abrasive souring powder can leave scratch marks on polished surfaces.Tannin (tea) stains and oily deposits in coffee urnsTannin stains - soak in a hot solution of washing soda i.e. sodium carbonate. Coffee deposits - soak in a hot solution of baking soda (sodium bicarbonate).These solutions can also be applied with a soft cloth or sponge. Rinse with clean water. Satisfactory on most surfaces.Adherent hard water scales and mortar/cement splashes10-15 volume % solution of phosphoric acid. Use warm, neutralise with dilute ammonia solution, rinse with clean water and dry6. Alternatively soak in a 25% vinegar solution and use a nylon brush to remove deposits.Proprietary formulations available with surfactant additions. Take special care when using hydrochloric acid based mortar removers .Heating or heavy discolourationa) Non-scratching cream or polish e.g. Solvol Auto Chrome Metal Polish b) Nylon-type pad, e.g. 'Scotchbrite'a)Creams are suitable for most finishes, but only use 'Solvol' on bright polished surfaces. Some slight scratching can be left.b)Use on brushed and polished finishes along the grain.Badly neglected surfaces with accumulated grime depositsA fine, abrasive paste as used for car body refinishing, e.g. 'T-cut' rinsed clean to remove all paste material and dried1.May brighten dull finishes. To avoid a patchy appearance, the whole surface may need to be treated.Paint, graffitiProprietary alkaline or solvent paint strippers, depending upon paint type. Use soft nylon or bristle brush on patterned surfaces.Apply as directed by manufacturer.