Pengaruh Variasi Media Pendingin dan Variasi Holding Time pada Proses Perlakuan Panas terhadap Sifat Mekanik dan Struktur Mikro pada Baja Mangan Fe-10.5Mn-1.3Mo-2.5Ni

Abstract

The characteristics of the Fe-10.5Mn-1.3Mo-2.5Ni steel alloy results of casting were further investigated after a heat treatment process was carried out through 2 stages, namely heating from room temperature to 700 ° C with a holding time of 3 hours, then raising it again to a temperature of 1000 ° C. with variations in holding time for 1 hour, 2 hours, and 3 hours followed by quenchant in water and 1.5% NaCl solution. The results showed that heat treatment followed by water quenching has produced higher hardness up to 2 hours holding time and subsequently decreased at longer holding time.. Meanwhile, the hardness value gradually increased with a longer holding time in 1.5% NaCl solution cooling process. The highest hardness value reached 235 BHN at the 2 hours holding time followed by water cooling. The results of the impact value of water and NaCl 1.5% varied. In water, the holding time of 1 hour increased at the holding time of 2 hours and decreased at the holding time of 3 hours. Meanwhile, in 1.5% NaCl, the highest value of holding time is 1 hour, then it decreases at 2 hours holding time and increases in 3 hours holding time. The highest impact value of 101 Joule was resulted in heat treatment with 1 hour holding time followed by 1.5 NaCl solution rapid cooling. The microstructure showed that undissolved carbides which dispersed at the grain boundaries and within the grains affecting on high hardness value.

Keywords

• holding time
• quenchant
• heat treatment