No abstract

No abstract

This paper aims at a systematic comparison of effect of single, double and triple pass welding on heat affected zone and tensile strength of AISI 304 stainless steel and chrome-manganese austenitic stainless steel. Degree of sensitization (DOS) increased with increase in number of passes and highest DOS (35.53%) was obtained for triple pass welding of chrome-manganese austenitic stainless steel. The decrease in tensile strength is relatively more in chrome-manganese austenitic stainless steel as compared to AISI 304 SS. The mode of failure for AISI 304 SS was ductile fracture, whereas chrome-manganese austenitic stainless steel failed due to intergranular brittle fracture.KEY WORDS: AISI 304 stainless steel; chrome-manganese austenitic stainless steel; shielded metal arc welding; heat affected zone; fractography; electron probe micro analysis.

No abstract

No abstract

No abstract

Chrome-Manganese steel is relatively new steel as compared to its counterpart 304 series stainless steels. There are relatively few studies on the welding behaviour of low nickel Cr-Mn stainless steel (in particular, on the effect of heat input on the microstructural developments). In the present investigation, a low nickel chrome-manganese stainless steel was welded (shielded metal arc welding process) to see the effect of heat input on the microstructural evolution and mechanical properties. At higher heat inputs (404.2 J/mm and 528.1 J/mm), tensile strength and hardness are lower compared to low heat input (316.6 J/mm). Fractographic investigation of the tensile tested specimen revealed dimple-like ductile fracture. An attempt was also made to evaluate the phases incorporated in the investigated steel using Schaeffler diagram.

In the present investigation effect of austenitic fillers namely E308, E309 and E310 on microstructural and mechanical properties of ultra-low nickel austenitic stainless steel weldment was analysed. The WRC-1992 diagram has been used to predict δ-ferrite and solidification mode of weld metal. Microstructural exploration confers the variation in magnitude and morphologies of δ-ferrite for different Cr eq /Ni eq ratio. It was observed that greater amount of δferrite resulted in improved tensile strength. On the other hand, it lowered the impact strength of weld joint. The results indicated that E308 exhibits higher hardness and tensile strength, whereas E310 demonstrates higher impact strength and this may be attributed to the variation in δ-ferrite content and solidification mode. During tensile test joints failed in heat affected zone for all weld specimen. Surface morphology of fragmented specimens was analysed using scanning electron microscopy and different morphologies were recognised for samples failed before and after Strauss test.