Comparison of metastable phases induced by heat treatment of unmilled and milled cobalt powders

被引：3

作者：

Bolokang, A. S. ^{[1
]}

Phasha, M. J. ^{[2
]}

Bhero, S. ^{[1
]}

机构：

[1] Univ Johannesburg, Dept Engn Met, ZA-2028 Doornfontein, South Africa

[2] CSIR, ZA-0001 Pretoria, South Africa

来源：

INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS | 2013年 / 36卷

关键词：

Cobalt; Water quenching; Metastable phases; Mechanical milling; XRD; ALLOTROPIC TRANSFORMATION; NANOCRYSTALLINE; MICROSTRUCTURE; TITANIUM;

D O I：

10.1016/j.ijrmhm.2012.08.001

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The sintered and water quenched compact samples were prepared from unmilled and milled Co powders. Characterisation was performed by differential scanning calorimetry, scanning electron microscopy and X-ray diffraction techniques. Several metastable phases were obtained upon sintering and quenching. However, more metastable phases were induced on quenching the milled-sintered samples due to introduction of large number of defects in addition to those induced by milling. Micro hardness values for unmilled sintered samples were the lowest while those of 30 h milled-sintered samples were the highest. The current study reveals that the two FCC metastable phases obtained by quenching unmilled powder were similar to those found in milled-sintered samples. (c) 2012 Elsevier Ltd. All rights reserved.

引用

页码：111 / 115

页数：5

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