@article{murty_mathew_2004, title={Nondestructive monitoring of structural materials using automated ball indentation (ABI) technique}, volume={228}, ISSN={["1872-759X"]}, DOI={10.1016/j.nucengdes.2003.06.006}, abstractNote={Materials used for high temperature components in nuclear power generation, aerospace, chemical and process plants undergo changes in their microstructure during operation in service leading to degradation in their mechanical properties. Monitoring the progressive changes in the mechanical properties is very important from the point of view of ensuring the structural integrity of the components and also for possible extension of their useful service life. Nondestructive methods for directly evaluating the mechanical properties are required for the success of any materials aging and life management program. In this paper, we describe an innovative automated technique based on ball indentation that can be used for laboratory and field applications in order to measure the mechanical and fracture properties of materials. Typical results from laboratory studies on engineering materials are also presented.}, number={1-3}, journal={NUCLEAR ENGINEERING AND DESIGN}, author={Murty, KL and Mathew, MD}, year={2004}, month={Mar}, pages={81–96} } @article{mathew_movva_murty_2000, title={Deformation mechanisms in tin and tin-based electronic solder alloys}, volume={171-1}, ISBN={["0-87849-842-7"]}, ISSN={["1013-9826"]}, DOI={10.4028/www.scientific.net/kem.171-174.655}, journal={CREEP AND FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES}, author={Mathew, MD and Movva, S and Murty, KL}, year={2000}, pages={655–662} } @article{mathew_yang_movva_murty_2000, title={High temperature deformation characteristics of tin-based solder alloys: Application to electronic packaging}, volume={53}, number={3}, journal={Transactions of the Indian Institute of Metals}, author={Mathew, M. D. and Yang, H. and Movva, S. and Murty, K. L.}, year={2000}, month={Jun}, pages={369–379} } @article{mathew_murty_rao_mannan_1999, title={Ball indentation studies on the effect of aging on mechanical behavior of alloy 625}, volume={264}, ISSN={["0921-5093"]}, DOI={10.1016/s0921-5093(98)01098-3}, abstractNote={The effect of aging on mechanical behavior of Alloy 625 was investigated using the non-destructive Stress–Strain Microprobe (SSM) system. SSM is based on an automated ball indentation (ABI) technique, and involves multiple indentations by a small spherical indenter at a single penetration location under strain-controlled conditions. The technique permits evaluation of mechanical properties such as yield strength, ultimate tensile strength, strength coefficient and strain hardening exponent. Alloy 625 was aged at six different temperatures in the range of 873–1173 K for 500 h each. ABI tests were carried out at room temperature and at 473 K. The variation of yield and ultimate tensile strengths with aging temperature exhibited a peak in strength following aging at 973 K. The peak stress was 1.5 times the strength of the unaged material, and the strength after aging at 1173 K was nearly equal to that of the unaged material. The peak in strength is attributed to the precipitation of the γ” phase. The fall in strength due to aging above 973 K is attributed to the precipitation, growth and dissolution of δ-phase precipitates. These studies demonstrate that ABI can be used as a non-destructive technique to determine changes in mechanical properties of nickel base alloy components due to aging.}, number={1-2}, journal={MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING}, author={Mathew, MD and Murty, KL and Rao, KBS and Mannan, SL}, year={1999}, month={May}, pages={159–166} } @article{murty_miraglia_mathew_shah_haggag_1999, title={Characterization of gradients in mechanical properties of SA-533B steel welds using ball indentation}, volume={76}, ISSN={["0308-0161"]}, DOI={10.1016/S0308-0161(99)00006-X}, abstractNote={Gradients in mechanical and fracture properties of SA-533B steel welds were studied using ball indentation technique. The local stress–strain behaviors of different microstructural zones of the weld were determined at various temperatures. Gradients in the strength of the base metal, weld metal and the different positions in the heat affected zone were observed to be consistent with the changes in the microstructure. The maximum in yield and the corresponding minimum in indentation energy to fracture occurred at around 1 mm from the fusion line.}, number={6}, journal={INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING}, author={Murty, KL and Miraglia, PQ and Mathew, MD and Shah, VN and Haggag, FM}, year={1999}, month={May}, pages={361–369} } @article{mathew_murty_1999, title={Non-destructive studies on tensile and fracture properties of molybdenum at low temperatures (148 to 423 K)}, volume={34}, ISSN={["0022-2461"]}, DOI={10.1023/A:1004547709783}, number={7}, journal={JOURNAL OF MATERIALS SCIENCE}, author={Mathew, MD and Murty, KL}, year={1999}, month={Apr}, pages={1497–1503} }