ABSTRACT

Conventional Austempered Ductile Irons (ADI) are lacking in adequate wear resistance. Introduction of hard alloy carbide phase in the microstructure by strong carbide formers imparts wear resistance. Deep cryogenic treatment subsequent to austempering is another way to improve the wear resistance without a major reduction in toughness. The present study encompasses the microstructural evolution following deep cryogenic treatment and the resultant bulk hardness, Charpy impact toughness and dry sliding wear of two vanadium contained (0.1% and 0.3%) carbidic austempered ductile irons. The irons were austempered at two temperatures viz. 300⁰ C and 350⁰ C for 30, 45, and 60 minutes and which is accompanied at −196⁰ C either by deep cryogenic treatment or air-cooled. EDS & XRD (X-ray Diffraction), Optical and Scanning Electron Microscopy analysis have characterized the microstructural features. Increase in vanadium content and cryo-treatment result in a prominent combination of wear resistance and impact toughness.

摘要

传统的奥氏体球墨铸铁 (ADI) 缺乏足够的耐磨性。通过强碳化物形成剂在微观结构中引入硬质合金碳化物相赋予耐磨性。等温淬火后的深冷处理是另一种提高耐磨性而不显着降低韧性的方法。本研究包括深冷处理后的微观结构演变以及两种含钒（0.1% 和 0.3%）碳化物奥氏体球墨铸铁的整体硬度、夏比冲击韧性和干滑动磨损。铁杆在两个温度下进行奥氏体回火，即。300 ⁰  C 和 350 ⁰  C 持续 30、45 和 60 分钟，并伴随 -196 ⁰ C 通过深冷处理或风冷。EDS 和 XRD（X 射线衍射）、光学和扫描电子显微镜分析表征了微观结构特征。钒含量的增加和低温处理导致耐磨性和冲击韧性的显着结合。