Digvijay Singh

National Institute for Materials Science | NIMS · Structural Materials Unit

This article investigates the microstructure evolution and corrosion response of surface mechanical attrition treated (SMAT) AZ91D magnesium alloy. In-depth transmission electron microscopy and combined isothermal calorimetry and pressure measurement technique, a novel and powerful tool for in situ monitoring of the magnesium corrosion process, are...

The present study investigates the microstructural and passivation behavior of surface mechanical attrition treated (SMAT) AISI 304 stainless steel in a 0.6 M NaCl solution at room temperature. SMAT process, which is more advanced than the classical shot-peening, causes 2-3 times improvement in surface hardness of the steel. Ball size, a vital SMAT...

The surface behaviour of surface mechanical attrition treated (SMATed) and plasma-nitrided AISI 2205 and AISI 304L steels was investigated in the present study. The intersection of the mechanical twins formed the submicron-size rhombic blocks in the surface region of the SMATed AISI 304L steel. However, such microstructural feature was absent in th...

The present study investigates the high-temperature oxidation behaviour of nanostructure surface layered AISI 304L stainless steel. A severely deformed layer of ∼300 μm thickness, consisting of nanoscale grains (∼40 nm size) in the topmost region, is successfully developed using the surface mechanical attrition treatment (SMAT) process. The SMATed...

The present study deals with the properties of boronized and non-boronized low-alloy steel (34CrAlMo5-10). Specimens are characterised using microscopy, various spectroscopic techniques, nanoindentation, surface profilometer, and tribometer. The boronized region contains (i) (Fe, M)2B columns and (ii) matrix between the columns. Nanoindentation stu...

In the present work, tribological behavior of surface mechanical attrition treated (SMAT) AISI 2205 steel was studied under dry and lubricated conditions using different loads. SMAT process parameters were optimized using the Taguchi technique for maximum output response of surface roughness. It was found that the SMAT process altered the surface m...

The surface behaviour of surface mechanical attrition treated (SMATed) and plasma-nitrided AISI 2205 and AISI 304L steels was investigated in the present study. The intersection of the mechanical twins formed the submicron-size rhombic blocks in the surface region of the SMATed AISI 304L steel. However, such microstructural feature was absent in th...

Wear behaviour of the AISI 4140 steel specimens with various surface conditions was tested against the DLC-coated boronized disc of AISI 4140 steel. Specific wear rate and coefficient of friction (COF) of the as-boronized (AB) pins at 100 and 150 N loads were substantially lower than the boronized–polished (B-P) pins. COF of AB pins was in the rang...

Wear behaviour of the AISI 4140 steel specimens with various surface conditions was tested against the DLC-coated boronized disc of AISI 4140 steel. Specific wear rate and coefficient of friction (COF) of the as-boronized (AB) pins at 100 and 150 N loads were substantially lower than the boronized–polished (B-P) pins. COF of AB pins was in the rang...