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Abstract：
In this paper, enhancing the tribological characteristics of novel cast metallic materials-hybrid multi-component cast irons-by applying a strengthening heat treatment is described. The experimental materials were the cast alloys of a nominal composition (5 wt.% W, 5 wt.% Mo, 5 wt.% V, 10 wt.% Cr, 2.5 wt.% Ti, Fe is a balance) supplemented with 0.3-1.1 wt.% C and 1.5-2.5 wt.% B (total of nine alloys). The heat treatment was oil-quenching followed by 200 °C tempering. The quench temperature (QT) varied in the range of 900-1200 °C, with a step of 50 °C (with a 2-h holding at QT). The correlation of the QT with microstructure and properties was estimated using microstructure/worn surface characterization, differential scanning calorimetry, hardness measurement, and three-body-abrasive wear testing (using Al2O3 particles). The as-cast alloys had a multi-phase structure consisting of primary and/or eutectic borocarbide M2(B,C)5, carboborides M(C,B), M7(C,B)3, M3(C,B), and the matrix (ferrite, martensite, pearlite/bainite) in different combinations and volume fractions. Generally, the increase in the quenching temperature resulted in a gradual increase in hardness (maximally to 66-67 HRC) and a decrease in the wear rate in most alloys. This was due to the change in the phase-structure state of the alloys under quenching, namely, the secondary carboboride precipitation, and replacing ferrite and pearlite/bainite with martensite. The wear rate was found to be inversely proportional to bulk hardness. The maximum wear resistance was attributed to QT = 1150-1200 °C, when the wear rate of the alloys was lowered by three to six times as compared to the as-cast state. With the QT increase, the difference in the wear rate of the alloys decreased by three times. The highest abrasive resistance was attributed to the alloys with 1.1 wt.% C, which had a 2.36-3.20 times lower wear rate as compared with that of the reference alloy (13 wt.% Cr cast iron, hardness of 66 HRC). The effects of carbon and boron on hardness and wear behavior are analyzed using the regression models developed according to the factorial design procedure. The wear mechanisms are discussed based on worn surface characterization.
摘要：
在本文中,描述了通过应用强化热处理来增强新型铸造金属材料-混合多组分铸铁的摩擦学特性。实验材料是标称组成的铸造合金(5重量%。%W,5wt.%Mo,5wt.%V,10wt。%Cr,2.5重量。%Ti,Fe是余量）补充0.3-1.1wt。C和1.5-2.5重量%。%B(共9种合金)。热处理是油淬火,然后是200°C回火。淬火温度（QT）在900-1200°C的范围内变化，步骤为50°C（在QT下保持2小时）。使用微观结构/磨损表面表征估计QT与微观结构和性能的相关性，差示扫描量热法,硬度测量,和三体磨料磨损测试（使用Al2O3颗粒）。铸态合金具有由初晶和/或共晶碳化硼M2（B，C)5，碳硼化物M(C，B),M7(C,B)3、M3(C、B),和基体(铁素体，马氏体,不同组合和体积分数的珠光体/贝氏体）。一般来说,淬火温度的升高导致硬度逐渐增加（最大为66-67HRC），并且大多数合金的磨损率降低。这是由于淬火时合金的相结构状态发生变化，即,次级碳硼化物沉淀，用马氏体代替铁素体和珠光体/贝氏体。发现磨损率与体积硬度成反比。最大耐磨性归因于QT=1150-1200°C，与铸态相比，合金的磨损率降低了三到六倍。随着QT的增加,合金的磨损率差异降低了三倍。最高的耐磨性归因于具有1.1wt。%C,与参考合金（13wt。%Cr铸铁,66HRC的硬度)。使用根据因子设计程序开发的回归模型，分析了碳和硼对硬度和磨损行为的影响。基于磨损表面表征讨论了磨损机理。
