Structure Control and Strength of Graphite Crystallized High Alloy White Cast Iron

石墨结晶高合金白口铸铁的组织控制与强度

基本信息

批准号：
09650754
负责人：
ASO Setsuo
金额：
$ 1.98万
依托单位：
AKITA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09650754/
关键词：
chromium white cast iron chromium carbide cast composite material sliding wear coefficient of friction roll material heat treatment wear 黒鉛摩耗圧縮強度ひずみ速度依存性ひずみ速度依存症

项目摘要

Graphite crystallized chromium white cast iron is composed of the three-phase composite structure of carbide, iron matrix, and graphite. The flakily graphite crystallized chromium white cast iron (FG alloy) becomes the spheroidal graphite crystallized type (SG alloy) by the spheroidizing. The deformation of the matrix mainly governed high temperature deformation of these alloys on the high temperature compression test. In the meantime, the strength depended on the property of the carbide. Though compression strength was improved by the graphite spheroidizing at the temperature under Tm/2, in the temperature over Tm/2, it did not change. In addition, the strength hardly lowered by the existence of the graphite, when it was compared in usual high chromium white cast iron. The difference of each alloy was remarkable for the sliding wear resistance by Okoshi type test in the high friction velocity side. The SG alloy was most excellent in the wear resistance, and the order of the following FG alloy and 2.6C-15Cr alloy. FG alloy and SG alloy changed after the heat treatment over HRC60 from HRC44 of as-cast, while it was also about HRC55 in either case, each 2.6C-15Cr alloy. However, the drastic improvement on wear resistance through the heat treatment could not be observed. The relation between wear amount and friction velocity becomes generously the low velocity side for the profile with the peak. In the meantime, these tend to be completely reverse for the friction coefficient, since the low velocity side is minimized. In comparison with normal high chromium white cast iron, graphite crystallized chromium white cast iron is also over par or over it on strength and wear resistant. In addition, it may be able to widely use as an wear-resistant material, because that the graphite keeps the oil in lubricated condition is anticipated. Moreover, both heat-resistance and corrosion resistance seem to be also excellent, since the matrix is retained austenite in the as cast.

石墨结晶铬白口铸铁由碳化物、铁基体和石墨的三相复合组织组成。片状石墨结晶型铬白口铸铁（FG合金）通过球化处理成为球状石墨结晶型（SG合金）。在高温压缩试验中，基体的变形主要控制这些合金的高温变形。同时，强度取决于碳化物的性能。尽管在Tm/2以下的温度下石墨球化提高了压缩强度，但在Tm/2以上的温度下压缩强度没有变化。另外，与通常的高铬白口铸铁相比，强度几乎不会因石墨的存在而降低。通过大越型试验，在高摩擦速度侧，各合金的耐滑动磨损性差异显着。 SG合金的耐磨性最优异，其顺序依次为FG合金和2.6C-15Cr合金。 FG合金和SG合金在热处理后从铸态的HRC44变化到HRC60以上，而2.6C-15Cr合金的两种情况也都变化到HRC55左右。然而，通过热处理并没有观察到耐磨性的显着改善。对于具有峰值的轮廓，磨损量和摩擦速度之间的关系明显地变为低速侧。同时，由于低速侧被最小化，因此对于摩擦系数而言，这些往往完全相反。与普通高铬白口铸铁相比，石墨结晶铬白口铸铁的强度和耐磨性也超过或超过普通高铬白口铸铁。此外，它可能能够广泛用作耐磨材料，因为石墨可以使油保持润滑状态。此外，由于基体在铸态时为残余奥氏体，因此耐热性和耐腐蚀性似乎也优异。