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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.

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The use of chrome-manganese stainless steels (Cr-Mn SSs) of 200-series grade has tremendously increased in past few years in various applications like construction, home accessories, office appliances, light poles etc. Their mechanical properties, weldability and corrosion/oxidation resistance provide the best all-round performance stainless steels at relatively low cost. Therefore, they serve as an appropriate alternative to 300-series stainless steels now days. Similar to 300-series steels, Cr-Mn SSs are also submitted to various fabrication practices like welding, hot rolling, cold working, solution annealing or stress relieving processes. This leads to change in their grain size due to higher operating temperature during service. The grain size has a major influence on the intergranular corrosion (IGC) developed due to sensitization phenomena. Several investigations have been made on the influence of grain size on IGC behaviour of 300-series stainless steels, but this information about Cr-Mn SS is scanty till now. Therefore, in this paper an attempt has been made to evaluate the effect of grain growth on degree of sensitization (DOS) of Cr-Mn SS and finally concluded that the DOS decreases with increase in grain size.

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In the present investigation, an attempt has been made to investigate the replacement compatibility of conventional austenitic stainless steel (316L) with low-Ni austenitic stainless steel (201) by employing their dissimilar welding using gas tungsten arc welding technique with varying heat input. The effects of heat input on the microstructural, mechanical, and corrosion properties were studied. The result depicts the balanced austenite/ferrite content in the fusion zone for both the heat inputs. The low heat input process, which results in a faster cooling rate, demonstrates higher tensile strength and microhardness. Similarly, the pitting corrosion resistance of the fusion zone demonstrates better properties on the low heat input process attributed to the lesser dendritic length and lesser interdendritic arm spacing.

In the present investigation, the dissimilar metal butt joints between low nickel high nitrogen 201 stainless steel and conventional 304 stainless steel were prepared by shielded metal arc welding process with two different llers, E308L and E309L. The effects of llers, along with variation in solution annealing temperature as 1050 C and 1100 C, on the microstructural characteristics, mechanical properties, and intergranular corrosion behaviour of dissimilar weldments were investigated. The primary δ-ferrites of fusion zone were transformed into austenite at the solution annealing temperature for both the llers and the transformation rate was accelerated with the increased solution annealing temperature. This led to a reduction in the ferritic-austenitic interface and subsequently improved the corrosion resistance. The double loop electrochemical potentiodynamic reactivation test was performed to measure the degree of sensitization. The fracture surface examination of weldments revealed the presence of a brous structure before the solution annealing treatment and demonstrated a ductile failure. After the solution annealing treatment, the ferrite to austenite transformation treatment led to a river like morphology and indicated for brittle fracture.