Effects of Nitriding-Quenching and Carburizing-Quenching on Wear Properties of Industrial Pure Iron

Abstract

The wear properties of industrial pure iron treated by nitriding-quenching and carburizing-quenching were investigated. Both the nitrogen martensite and carbon martensite produced by each treatment exhibited the same high degree of wear resistance. The results of sliding tests showed that the nano-indentation hardness near the surfaces of both samples had increased. The surface hardening of the nitrogen martensite was more noticeable than that of the carbon martensite. EBSD analysis revealed that plastic strain had been induced on a relatively large scale (around 20 μm) after sliding in the case of the nitrogen martensite. It was found that the high wear resistance of the nitrogen martensite led to strain hardening through the effect of the load applied in the sliding test.

Enhancing Wear Resistance in Functionally Graded Metallic Components: Insights from Nanoindentation and Mechanical Analysis

“…Both surface layers exhibited higher wear resistances as compared with those of the untreated hot-rolled specimens under the no-lubrication condition in a ring-on-plate sliding test. In another study [25], a similar wear resistance was obtained for pure iron treated via NQT and CQT. However, a specific way to estimate the wear resistance has not been established yet in FGMs.…”

“…The H profiles obtained in the direction perpendicular to the specimen surface are shown in Figure 1 [24,25]. The near-surface H (2 µm from the surface) of NQT913 is slightly higher than that of NQT1033.…”

“…The near-surface H value of CQT1203 (12,700) is greater than that of NQT913 (9800) and NQT1033 (9300). It exhibits a gradual decrease to a depth of 40 µm, ultimately reaching a constant value of 9800 N/mm 2 [25], which is attributed to the carbon diffusion treatment (1113 K × 1.8 ks). The H of the No HT specimen is consistently lower than those of the heat-treated specimens, maintaining a constant value of 2000 N/mm 2 near the surface.…”

“…The correlation between the wear distance and wear volume determined by conducting ring-on-plate sliding tests is presented in Figure 7 [24,25]. Pure iron (No HT) shows relatively low hardness, so the initial amount of wear is high.…”

“…Coated materials typically contain a uniformly hardened layer with a thickness of several micrometres on the surface, while carburised steels exhibit a hardness range of 10-100 µm [24][25][26]. Therefore, it is crucial to assess H and E r at the micrometre scale and investigate the effects of changes in H and H/E r along the depth direction on the wear resistance of CQT-treated and NQT-treated steels.…”