Performance stainless steel plate

In addition to the overall heat transfer coefficient of thermal conductivity of metals depends on the metal, but also depends on other factors. In most cases, the film heat transfer coefficient or rust and surface condition of the metal. Stainless steel can keep the surface clean, so it is better than the thermal conductivity of the higher thermal conductivity of other metals. Liaocheng Suntory provide eight stainless steel, stainless steel plate excellent technical standard stainless steel plate corrosion resistance, bending workability and toughness of welded portion, and punching workability of weld high-strength 409 stainless steel plate and its manufacturing method. Specifically is to contain C: 0.02% or less, N: 0.02% or less, Cr: more than 11% but less than 17%, an appropriate content of Si, Mn, P, S, Al, Ni, and satisfies 12≤Cr Mo 1.5Si≤ 17,1≤Ni 30 (CN) 0.5 (Mn Cu) ≤4, Cr 0.5 (Ni Cu) 3.3Mo≥16.0,0.006≤CN≤0.030 stainless steel plate heated to 850 ~ 1250 ℃, then subjected to 1 ℃ / s the cooling rate of the above heat treatment. Such organizations can become more than 12% volume fraction of martensite, 730MPa above high strength, corrosion resistance and bending properties, HAZ toughness of high-strength stainless steel plate 304. Reuse containing Mo, B, etc., can significantly improve the punching workability weld.

Ultra-low carbon ferritic stainless steel cold-rolled plate process

Factors affecting cold-rolled sheet with a body-centered cubic crystal structure of texture formation are:

(1) chemical composition. Increasing the chromium content ferritic stainless steel can be formed in favor of forming properties of texture components in the plate rolling process, the stabilizing elements Nh will strengthen austenite deformation texture, which led to a transformation texture y strengthening;

(2) solid solution elements and two-phase particles. Solute C atom of rotation ferrite grains rolling great impediment exists a two-phase solid solution alloying elements and particles does not affect the ferrite rolling texture components, but a solid solution alloy elements and the presence of two-phase particles can affect the degree of ferrite grains in the rolling process to stabilize the orientation of rotating them. ri, Nl1 added to help ferritic rolling texture to stabilize the rotation orientation;

(3) thermal processing. Such as low carbon steel with finishing temperature lower when ferrite region rolling, {111} recrystallization texture will be significantly enhanced;

(4) cold rolling reduction;

(5) annealing process, including temperature and time.

1 Materials and methods

Experimental ultra-low carbon steel is Crl8 ferrite laboratory vacuum induction furnace and rolling of the three components of 409 stainless steel plate. Cast ingot was forged blank size is 30mm thick x240mm wide × (560 ~ 660) mm long, for three billets were six times rolled, the heating temperature 1070 ℃, finishing temperature 851 ℃, hot-rolled total pressure under 88%, the hot rolled sheet having a thickness of 3.5mm, and finally cold rolled to 1.0mm sheet.

Taking into 1mm thick cold-rolled sheet width x28mm x20mm long rectangular specimen, wherein the length direction is the rolling direction. With a salt bath furnace at 850 ℃ cold rolled specimens condition 0 ~ 15min isothermal annealing at different times, according to the reply recrystallization stage determine the degree of change in hardness curve complete recrystallization, select Done to continue holding 3min after recrystallization sample extend the cut direction 7mm, polished to 1500 grit grinding section, the final adoption FeC1: HC1: H, O mass ratio of 1:10:20 in etchant etching, optical microscope photographs, According to GB / T6394-2002 ~ determination of the average grain size of metal "in grain size rating.

2 Results and discussion





Cr18-3 with the other two different orientations of its fiber texture density strength of 12.247. The reason may be Nb leads to inhibition of recrystallization texture development is not sufficient, while the original {001} texture strong, disappeared in the subsequent stage of the annealing is slow, still leave a certain proportion of damage formability Cr18-1 {001} <110> orientation texture.

Mechanical properties of ultra-low carbon 304 stainless steel sheets Cr18 annealed cold rolled sheet and formability of experimental data, the yield strength of Nb single stable Cr18-1 annealed cold rolled sheet and the highest tensile strength, and Ti, Nb double stabilized Cr18-2 secondly, ] ri single stable Crl8-3 lowest strength.

3 Conclusions

(1) Nb single stabilized recrystallized grains Crl8 cold rolled sheet after annealing treatment was small, high yield and tensile strength, but poor formability, r value is low, reach deep drawing timber requirements.

(2) Although the ri single stabilized Crl8 recrystallized grain size of the largest cold-rolled sheet, the intensity is not high, but the plastic is best conducive to forming properties of the {111} plane texture orientation density higher strength, its r value can reach 1.55, in line with the requirements of deep-drawing timber.

(3) Ti, Nb double stabilized recrystallized grain size Crl8 moderate cold rolled sheet, the r value reached 1.48, in line with the requirements of deep-drawing timber.
Average grain diameter and grain size level are: 0.18Nb; (e) Crl8-3,0.21Ti add Crl8 ferritic stainless steel cold rolled sheet grain 0.29% Nb of most small and uniform, because Nb in steel solid solution existence and carbonitride precipitation and steel C, N phase formation of niobium, Nb atoms in solid solution enrichment at the grain boundaries, and the lower the grain, so niobium has strongly drag the grain boundary mobility, this effect is much higher than the solution of titanium. In addition, the small dispersed niobium carbonitride NbC, NbN, Nb (CN) can stop pinning dislocations and subgrain boundary migration of grain growth with a strong impediment.

Antibacterial stainless steel

In the production of kitchen equipment, medical equipment, toiletries and cleaning decoration, people have been looking forward to both the shape of the metal new antibacterial material can appear.
Both structural and functional properties of new materials - both antibacterial stainless steel mechanical properties of structural materials, functional materials have physical and chemical properties, it is like that with the general 409 stainless steel plate decorative and landscaping as a member, as well as anti-bacterial self-cleaning effect of sterilization.
Data show now widely used antibacterial agent mainly organic antibacterial agents and inorganic antibacterial agent categories. Organic antibacterial agent has a long history in the medical field has been widely used, mainly in the use of spray or immersion. But they are in safety, durability, broad-spectrum antimicrobial resistance, heat resistance insufficient, especially for serious damage to humans and the environment can not be used on many occasions. Inorganic antimicrobial agent is mainly used as an additive, made with antibacterial fabric, plastic products, activated carbon, sanitary ceramics, etc., use of increasingly widespread. But in the heat, wear and corrosion resistance, strength and formability, can not meet the many needs of everyday use. Therefore, in the manufacture of kitchen machinery, medical equipment, bathroom cleaning supplies and carry out renovation, you must use has an antibacterial effect and shapes, appearance of metal products. This 304 stainless steel coil has antibacterial effect of the new birth, is an ideal product in people's minds.
Antibacterial stainless steel produced by antimicrobial resistance is divided into two types: type and their antimicrobial coating type. The former can be modified existing stainless steel products, i.e., on a stainless steel plated with a metal material with a germicidal, bactericidal effect, or other inorganic material, but the drawback is easy to wear, easy to aging, temperature changes and with the external environment and change, so that the loss of antibacterial stainless steel; the latter is added in the stainless steel production process some of the metallic elements having antimicrobial activity, through special processing to make antibacterial stainless steel itself, it does not have the disadvantages of the former, and low cost, easy to processing.
99.9% kill rate of E. coli, Staphylococcus aureus killing rate of 99.5%, 99.0% kill rate of Candida albicans, Kuhei bacteria kill rate of 86.6%. Common sense tells us that four kinds of bacteria are the most common ordinary life, to achieve such a killing effect, demonstrated broad-spectrum antibacterial antibacterial stainless steel.
With the material composition and microstructure of the adjustment and optimization, will further enhance the antibacterial effect. Antibacterial in an aqueous solution / antibacterial test, the antibacterial stainless steel test piece was immersed in the prepared bacteria liquid, by soaking at different times after the bacteria was observed in the number of colonies. The results showed that E. coli and Staphylococcus aureus killing rate of 90% -95%, indicating that the material in an aqueous solution can kill bacteria. That is not only able to kill bacteria in direct contact, but also to kill bacteria without direct contact through the diffusion of the solution.
Currently materials in the field for the "sterilization" and "antibacterial" there is no clear definition. Generally understood to inhibit bacterial antimicrobial development, growth and reproduction, sterilization is to kill microorganisms. Antibacterial stainless steel can not make it on the attached bacteria multiply, the bacteria are killed or inhibited at low level state, but does not change the intensity of ordinary stainless steel, corrosion resistance, aesthetic features, has a very broad application prospects. Look forward into people's homes.

Teach you how to identify counterfeit steel method

As we all know: a 409 stainless steel plate building as the human skeleton, which supports the building. If the steel is a problem, then the network architecture will certainly be a problem. Thus the steel quality directly affects people's lives and property safety.
Here we take a look at what some of the methods to identify fake steel:
     1. Shoddy steel prone to folding. Folding is formed on the surface of a variety of steel fold, this defect often throughout the product vertical. The reason is due to shoddy manufacturers of folding the pursuit of high efficiency, reduction is too large, resulting in the ears, it creates a rolling when folded down, it will crack when folded products bending, the strength of steel big drop.
     2. Steel is often shoddy appearance Pock phenomenon. Pock is caused due to a serious groove worn steel surface uneven irregular defects. Because of shoddy steel manufacturers have to pursue profits rolling groove most often exceeded.
     3. Shoddy steel surface is easy to produce scarring. There are two reasons: 1. Uneven shoddy steel materials, impurities. 2. Shoddy material manufacturers guides poorly equipped, easy to stick steel, easy to produce scarring after the roll bite of these impurities.
     4. Shoddy material surface easy to crack because it is blank adobe, adobe many pores, adobe in the cooling process due to thermal stress, cracks, after rolling there cracks.
     5. Shoddy steel easily scratched because shoddy material equipment is very easy to produce burrs, scratches steel surface. Deep scratches reduce the strength of steel.
     6. No shoddy steel metallic luster, pale red color of pig iron or similar, there are two two reasons, it is adobe blank. 2, shoddy-rolling temperature is not standard, they are visually steel temperature, so the region can not be prescribed by the austenite rolling, natural properties of steel can not be reached.
     7. Transverse reinforcement steel thin shoddy low, often sufficient dissatisfaction phenomenon, because manufacturers to achieve large negative tolerance, finished in front of a few larger reduction, iron-type small, hole filling dissatisfaction.
     8. Shoddy magnetism stainless steel oval cross-section, because the manufacturers in order to save material, the first two tracks finished roll reduction is too large, the strength of this steel is greatly decreased, and does not conform to the standard dimensions of rebar.
     9. Uniform quality steel components, high tonnage cold shears, cut the first end surface smooth and tidy, but due to poor material shoddy material, there are often cut off the meat first end face of the phenomenon, namely uneven, and no metallic sheen. And because of shoddy little head cut wood product manufacturers, end to end will be a big ears.
     10. Shoddy steel material containing impurities, the density of steel is small, and size tolerance serious, so in the absence of a vernier caliper case, you can check it weighed. For example, for steel 20 national standards set forth in the most negative tolerance of 5%, while its length 9M single theoretical weight of 120 kg, its minimal weight should be: 120X (l-5%) = 114 kg, weigh out the actual weight of a single smaller than 114 kg, it is shoddy steel, because it is more than 5% negative tolerance. Generally the whole amount commensurate would be better, mainly taking into account the cumulative error and probability theory problem.
     11. Diameter size shoddy steel fluctuations due; l, steel surface temperature instability of yin and yang. 2, the non-uniform composition of the steel. 3, due to poor equipment, low-intensity ground, rolling big bounce. There will be changes in the larger inner diameter of the same week, so easy to produce steel discontinuity break.
     12. Trademarks and printing high-quality materials are relatively standardized.
     13. Three steel 16 or larger diameter screw spacing between the two trademarks are over IM.
     14. Inferior longitudinal reinforcement steel rebar often wavy.
     15. Shoddy steel manufacturers because there is no traffic, so the package is relatively loose. Side of the oval.

stainless steel sheets Corrosion

Experience has shown that the degree of corrosion of the atmosphere varies from region to region . For ease of explanation , qiyi 409 stainless steel plate to be divided into four areas , namely: rural, urban , industrial areas and coastal areas.
Country is essentially pollution-free zone. Low population density of the area , only non-polluting industries.
Typical urban residential, commercial and light industrial areas , the region has a mild contamination , such as traffic pollution.
Industrial area of air pollution caused by heavy industry area . Contamination may be other gases formed in the gas fuel , such as sulfur and nitrogen oxides, or the release of chemical or processing plant . Particles suspended in air travel , as the deposition of dust or iron oxide generated 430 stainless steel sheets roduction also cause corrosion increases.