what Mean:McQuaid E.H.N?

霜月

There is a note on a drawing of spiral bevel wheel:Material to be supplied with McQUAID E.H.N. Grain size 6~8,single quench quality.
What is meant by "McQUAID E.H.N",please?

[ 本帖最后由 gl9855 于 2009-4-2 12:59 编辑 ]

察哈尔汗

应为粒度测试，称为麦奎德-爱恩试验。评定晶粒尺寸的一种方法。
只是听过大体方法，具体操作还是再找下资料吧。

[ 本帖最后由 察哈尔汗 于 2009-4-1 07:53 编辑 ]

霜月

Thank you very much!

bill_bush

McQuaid EHN Grain Size Test
Definition:  A method of assessing grain size. It consists of a test piece at 927℃ for 8 hours by slow cooling and subsequent microscopical examination. The grain size is measured at x100 magnification and compared to standard charts, the figures range from No. 1 - very coarse, to No. 8 - very fine.

Following URL:

http://www.metallography.com/grain.htm

This article descripts the evolution of grain size test methods in us and some other euro countrys.

[ 本帖最后由 bill_bush 于 2009-4-2 08:59 编辑 ]