STAINLESS STEEL
Stainless steel is normally referred as non-rusting steel. In metallurgy, it is a type of steel which has at least 10.5 % of chromium content in it. It does not normally corrode, rust or stain with water as ordinary steel does but does not mean it is fully stain proof. It is vulnerable to environments having low oxygen and high salinity. Most commonly, stainless steel is used in application in which both steel properties and corrosion resistance are required.
It contains sufficient amount of chromium to make an effective layer of chromium oxide which prevents further corrosion by blocking diffusion of oxygen to the steel surface.The available grades we have in stock are as follows:-
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SS420/1.2083
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SS431/1.4057
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SS303
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SS304
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SS316L
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1.2316
SS420/1.2083
420 Stainless Steel, a modification of 410, has a higher carbon content to increase hardness, improve strength and give better wear resistance. This type of steel maintains its best corrosion resistance in the heat treated condition.
Applications 420 stainless is widely used in medical and cutlery industries. It is suitable for applications such as surgical instruments, knives, hand tools, pump shafts and plastic moulds. 420 is not recommended for use in temperatures above the relevant tempering temperature, because of the reduction in mechanical properties. Hardening and Tempering Best corrosion resistance of 420 stainless is achieved when 420 is hardened and surface ground or polished. 420 is suitable for heat treatment up to 52 HRc or higher depending on the carbon content and size of the component.
SS431/1.4057
This grade is a medium range stainless steel but still quite enduring in many applications. It offers good corrosion resistance in mild marine and industrial atmospheres where high tensile and yield strength with excellent toughness are required.
Applications It is used widely in aircraft and marine industries, for components such as shafts, axles, pumps, valves, bolts and nuts. Suitable for applications requiring good strength, toughness combined with reasonable resistance to corrosion. Hardening and Tempering Heat the component slowly to 950-1020°C and hold until the temperature is uniform throughout the steel. After adequate soaking time, quench in oil or air cool. Temper as soon as tools are hand warm. Heat carefully to a suitable tempering temperature. Soak as required and then allow to cool in air. Double tempering is recommended. 431 stainless can be tempered at lower temperatures to achieve higher tensile strengths but with lower impact properties.
SS303 Stainless Steel
SS 303, part of the austenitic (non-magnetic) group, is one of the most machinable stainless steels due to its sulfur content. While sulfur enhances machinability, it slightly reduces corrosion resistance, making SS304 more corrosion-resistant. However, SS 303 maintains excellent toughness typical of austenitic grades. It is widely used in food-grade shafts, springs, and hygienic nuts and bolts.
Heat Treatment SS303 stainless steel cannot be hardened by heat treatment. Solution treatment or annealing can be done by rapid cooling after heating to 1010- 1120°C.
SS304 Stainless Steel
SS 304 is the most versatile and widely used austenitic(non-Magnetic) Stainless steel. It is used in heavily gauged parts for improved weldibility. One of its unique property is that it can be severely deep drawn thus making it a dominant grade to be used in applications like sinks & saucepans.
Other major applications include screws, nuts , bolts, tubing, sanitary ware and brewery, food, dairy & pharmaceutical production equipment. Heat Treatment SS304 stainless steel cannot be hardened by heat treatment. Solution treatment or annealing can be done by rapid cooling after heating to 1010- 1120°C.
SS316L Stainless Steel
SS316L is an austenitic (non-magnetic) stainless steel with added molybdenum which makes it more corrosion-resistant and tough compared to SS304. It is also more resistant to pitting and chemicals even at elevated temperatures. SS316L has good weldability and also reduces the possibility of lower corrosion resistance around welded areas.
Major applications of this SS grade include food preparation equipment especially in chloride environments, Oil & Gas industries, pharmaceutical industry, medical implants, fasteners and pulp & paper processing. Heat Treatment Like other Austenitic grades, it cannot be Hardened. However, Solution treatment or Annealing can be done by heating to a range between 1010- 1120°C and then cooling rapidly in air or water.
SS 1.2316
This grade is normally named as molybdenum-chrome steel with excellent corrosion and good polishing properties, even better than chrome steel (1.2083).It has good ductility and toughness due to improved micro-purity and structural homogeneity. Furthermore, it has good stress pressure resistance both in the center and on the surface.
Applications It is used in making molds for corrosive materials (PVC and recycled polymers), automotive industry, medical instruments, rubber pressing, dies and gauges, mechanical parts for extrusion presses like extrusion heads. Hardening and Tempering Pre-heat the component to 600-700°C and then take the temperature up to 1000-1040°C. Let it cool down in air.
DIN 1.2316 equivalent grade: X38CrMo16
C 0.33-0.45%
Si 1.00% max
Cr 15.50-17.50%
Mo 0.80-1.30%
Mn 0-1.50%
P 0.03% max
S 0.03% max
Ni 1.00% max
