Microstructure and dry sliding wear behavior of ultrafine-grained Co-30 at% Cr alloy at room and elevated temperatures

Zhao, Cancan1,2; Zhou, Jian3; Mei, Qingsong2; Ren, Fuzeng1

2019-01-05

10.1016/j.jallcom.2018.08.092

JOURNAL OF ALLOYS AND COMPOUNDS   影响因子和分区

0925-8388

1873-4669

Co-Cr-based alloys have been widely used as mechanical components where high wear-resistance is required. However, conventional Co-Cr alloys usually have coarse-grained microstructures with phase coexistence of both hexagonal close packed (hcp) epsilon-Co and face-centered cubic (fcc) gamma-Co. The wear resistance of the Co-Cr alloys could be further enhanced by grain refinement and exclusion of gamma-phase. Here, a Co-30Cr (at%) bulk alloy consisting of ultrafine-grained matrix of epsilon-phase and uniformly dispersed nanoscale precipitates of sigma-phase was fabricated by high energy ball milling and spark plasma sintering. Microstructure and dry sliding wear performance against alumina at room temperature and 600 degrees C were then investigated. The matrix and the precipitates have the average grain size of 227 nm and 16 nm, respectively. Hardness was determined to be 707 HV. The epsilon-Co matrix, ultrafine-grained microstructure and the uniformly dispersed nanoprecipitates enable the alloy with excellent wear resistance. Grain growth of the matrix grain was found as the key factor to be responsible for the increase of wear rate at 600 degrees C. Subsurface microstructures of the alloy show no significant plastic deformation after wear tests, which is attributed to high hardness of the alloy and very limited slip in hcp system. (C) 2018 Elsevier B.V. All rights reserved.

Co-Cr alloy Ultrafine-grained Dry sliding wear Microstructure

SCI ; EI

英语

第一 ; 通讯

Guangdong Innovative and Entrepreneurial Research Team Program, China[2016ZT06C279]

Chemistry ; Materials Science ; Metallurgy & Metallurgical Engineering

Chemistry, Physical ; Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering

WOS:000449486300033

ELSEVIER SCIENCE SA

20183405732384

Alumina ; Aluminum oxide ; Ball milling ; Binary alloys ; Cobalt alloys ; Grain growth ; Grain refinement ; Grain size and shape ; Hardness ; Microstructure ; Precipitation (chemical) ; Spark plasma sintering ; Wear of materials ; Wear resistance

Chromium and Alloys:543.1 ; Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals:549.3 ; Chemical Operations:802.3 ; Inorganic Compounds:804.2 ; Physical Properties of Gases, Liquids and Solids:931.2 ; Crystal Growth:933.1.2 ; Materials Science:951

MATERIALS SCIENCE

Web of Science

1.South Univ Sci & Technol, Dept Mat Sci & Engn, Shenzhen, Peoples R China
2.Wuhan Univ, Sch Power & Mech Engn, Wuhan, Hubei, Peoples R China
3.Soochow Univ, Shagang Sch Iron & Steel, Suzhou, Peoples R China

Zhao, Cancan,Zhou, Jian,Mei, Qingsong,et al. Microstructure and dry sliding wear behavior of ultrafine-grained Co-30 at% Cr alloy at room and elevated temperatures[J]. JOURNAL OF ALLOYS AND COMPOUNDS,2019,770:276-284.

Zhao, Cancan,Zhou, Jian,Mei, Qingsong,&Ren, Fuzeng.(2019).Microstructure and dry sliding wear behavior of ultrafine-grained Co-30 at% Cr alloy at room and elevated temperatures.JOURNAL OF ALLOYS AND COMPOUNDS,770,276-284.

Zhao, Cancan,et al."Microstructure and dry sliding wear behavior of ultrafine-grained Co-30 at% Cr alloy at room and elevated temperatures".JOURNAL OF ALLOYS AND COMPOUNDS 770(2019):276-284.