جستجوی مقالات مرتبط با کلیدواژه « فولاد پر منگنز آستنیتی » در نشریات گروه « فنی و مهندسی »

In this research, the effect of shot-peening treatment on the wear behavior of two types of high manganese austenitic steel (Fe-7Mn-0.6Si- 1.2C and Fe-17Mn-0.6Si-1.2C) was investigated. In this regard, two samples with various manganese contents of 7 and 17 weight percent are cast, respectively. In order to achieve a uniform structure of austenite into all samples, solution-annealing process is performed at temperature of 1100°C during 2h. Micro hardness measurement and tensile testing as well as wear test according to the rubber wheel-dry sand method are conducted on all heat-treated samples. Surfacing hardening treatment by using of shot- peening equipment is done during 15 and 30 mines on all samples. The results showed that when the percentage of manganese increased from 7 to 17% in the heat-treated samples, hardness and tensile strength values are increased and improved about 27% and 10%, respectively. The surface hardness of high manganese austenite steels is increased due to the applying surface work hardening with shot-pinning treatment. Thus, the highest hardness is observed in the shot-peened sample at time of 30 min. however, the highest hardness and wear %resistance are determined in the sample containing 7%Mn. The investigation of worn surfaces showed that the wear mechanism was abrasive mechanism. Moreover, the amount of and the depth of grooves are reduced with increasing of hardness values.

In this study, the wear behavior of early hardened high-manganese austenitic steel with a nominal composition of Fe-17Mn-1.5Cr-0.6Si-1.2C were studied. The hardening was introduced via two methods of applying uniform hammer blows and shot pining. For this purpose, samples were casting in sand molds, were solutionized annealing at the temperature of 1100 ° C for 2 hours and then quenched in water. The initial work hardening was introduced via uniform hammer blows with the applied load of 100 tons and the strike numbers of 300 and 600. Beyond this, some samples were hardened via shot pining for 15 and 30 minutes. The hardness, tensile and impact tests were performed on the samples to investigate the mechanical behavior of the samples. Beyond this, the wear test with the wheels using dry sand was also performed on the samples. To study the micro structure of the samples optical microscopy (OM) were used. Moreover, the scanning electron microscope (SEM) were used to investigate the worn out surface of the samples. Results show that the hardness of the samples increases due to cold work from 290 HV to 653 HV and 698 HV for the hammer blow with 600 strikes and shot pining for 30 minutes, respectively. It was also revealed that the best wear behavior was shown in the samples hardened for 30 minus with shot pining due to higher surface hardness in these samples.