Stainless steel is made of essential elements which include chromium, silicon, iron ore, nickel, carbon, nitrogen and manganese. The exceptional properties of the final alloy are arrived at by varying the quantities of the above elements. Stainless steel is notable for its excellent corrosion resistance, which depends on the amount of chromium in the alloy.
Stainless steel is highly versatile, so many stainless steel fabricating methods can be applied. The following are the standard stainless steel fabricating techniques:
Work hardening with stainless steel
In stainless steel fabrication, work hardening involves strengthening the material through deformation. Stainless steel tends to work harden faster than other types of steel, although the specific rate will always depend on the grade of the alloy. It is therefore ever essential to match the steel grade with the work-hardening treatment that it is best suited for. For example, austenitic stainless steel can usually be work hardened only by cold working.
Work hardening also increases the magnetism of stainless steel during the steel fabrication process. Grades with high work hardening rates show high levels of magnetic capacity after undergoing this treatment. Greater deformation is always achieved at slower forming speeds, and therefore, high-speed processes should be slowed down to improve their work hardening capacity.
Stainless steel machining
During the process of stainless steel fabrication, some grades develop resistance to chipping when they are alloyed with manganese sulfide. Addition of manganese sulfide causes decreased ductility and resistance to corrosion, so these grades have limited applications when it comes to machining. Machining can be improved by applying lubricants or coolants to the machines and keeping the cutting edges sharp.
Welding stainless steel
Although most types of stainless steel can be welded during the stainless fabrication process, not all of them can. The degree of efficiency of welding will depend on the grade undergoing the procedure. Consider the following factors when it comes to welding:
This specific grade is welding efficient and it works best for low thermal expansion.
Most austenitic grades are suitable for welding purposes. However, the product tends to be highly susceptible to sensitisation and inter-granular corrosion, especially on thicker products.
Ferritic stainless steel
They are less suitable or welding but some stabilised grades can be used or particular products. Sensitisation and low ductility can be overcome by post-heating the already welded material.
In conclusion, various considerations should be made during fabrication because not all the grades are suited for the different conditions that come along with these techniques of fabrication.