A Study of Microstructural Evolution of AISI D2 Tool Steel during Direct Partial Remelting Method

Fadzilah Adnan, Zainuddin Sajuri, and Zaidi Omar
Department of Mechanical and Materials Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
Abstract—Tool steels are difficult to weld using conventional fusion welding process. Therefore, in this study, a thixotropic property of metal was utilized to join an AISI D2 tool steel by using uncommon direct partial re-melting (DPRM) method. The aim of this study is to analyse the effect of DPRM on microstructural evolution and hardness property of the welded joint of D2 tool steel. The microstructural analysis showed that the inherent carbides in D2 tool steel fully dissolved when the heating temperature reached between 1250ºC and 1280⁰ ºC. Overall, the grain size and shape factor of DPRM samples were within the limit of semisolid processing parameter which are 100 μm and 2, respectively. Based on the microstructural evolution analysis, grain size, shape factor, and hardness value obtained, this study successfully affirmed that with suitable globular microstructure and high bonding quality a sound weld joint of D2 tool steel components can be attained at temperature range of 1280 ºC, 1300 ºC and 1320 ºC.
Index Terms—DPRM, microstructure, hardness, liquid fraction, D2 tool steel

Cite: Fadzilah Adnan, Zainuddin Sajuri, and Zaidi Omar, "A Study of Microstructural Evolution of AISI D2 Tool Steel during Direct Partial Remelting Method," International Journal of Mechanical Engineering and Robotics Research, Vol. 7, No. 6, pp. 689-693, November 2018. DOI: 10.18178/ijmerr.7.6.689-693
Copyright © 2016-2017 International Journal of Mechanical Engineering and Robotics Research, All Rights Reserved
E-mail: ijmerr@ejournal.net