Tempered Steel 1

[FNB8812]

I have a piece of alloy-steel round bar(4140) the dimension are 1/2 diameter and 4 long and the steel has been heat treated and tempered to 40-45 Rc I am heating up the end of the steel bar to about 1500 degrees for 10 seconds. My question is when I do this am I effecting the heat treatment or changing the properties of the steel in any way and is there a recommendations for cooling?

 

[TomDOT]

Neat article on flash heat treatment (less than 10 seconds) at ASM. I had just deleted this from old mail today, but hadn't dumped the trash yet.

http://www.asminternational.org/portal/site/

http://www/NewsItem/?vgnextoid=38336199868b0310VgnVCM100000621e010aRCRD

 

[CoryPad]

Yes you are affecting the properties. How you cool depends on what the part function is.

 

[BillPSU]

You are definitely effecting the properties of the steel. If nothing else you are doing further tempering of the steel reducing the hardness and tensile strength. Your process does not appear to be a controlled process so results will be variable.

Predictable results would require consistent processing. Control the temperature and length of time and cooling rate. Your environment may also need controlling by limiting oxygen and flame settings.

Bill