we are a job shop, one customer requires us not to use water (cold or hot, with anti-rust agent or not) to clean parts, because the metal parts is very sensative to get rust. the parts after process normally covered with machine oil. is there any way or equipment to remove oil. someone suggest a...
understanding that 1 or 2 RC difference may be within tolerance. however we have had this variance constantly, i.e. surf is harder than core. therefore difficult to attribute the difference to test tolerance.
another thing is that the parts, washers, are only two coins' thickness. i am not sure...
we heat treated some parts (4130) and then send to platter to chrome plating. after platting, a few parts have blister. platter claims that it is caused by the heavy scale on parts, and the scale was formed by baking the stamping oil into the parts in the heat treating process.
We start to wash...
we did some normal thru hardening job on 8740. the surface is 1 or 2 point (RC) harder than core. microscope shows no sign of carburization. why this happen? what we can do?
thanks
material 1075, shining washer parts. after oil quench, quench oil gives the parts a not so shine thin layer and looks dirty. if washed with regular hot water which rust prohibitive soap, the tempered parts will show soap scale. if temper without wash, the parts will still have slight blur. is...
kenvlach,
we use city water without di-ionize. the polymer ph is 8, and the quench solution is 9. is that a problem. what is the right ph i should maintain?
yush
arunmrao,
the wash process after oil quench left stain (not rust), probably from the soap used in wash tank, on the parts. and customer does not like it. the polymer gives gook looking to parts, but unfortunately some parts get rust. tomorrow i will do a ph test to the polymer according to...
we heat the parts, size of 5 cent coin, material 1075, to 1600 F and then quench at polymer water. then temper at 400 F. we always get some of parts, less than 5%, with rust stain. does anyone know how to avoid this.
by the way, we can not get required hardness if quenched in oil.
thanks,
yush
to confirm that the parts are 1-1/4" washer, made out of stamping steel sheets.
here is a strange thing. we run 2 batchs at two identical lines (same carbonitriding atomsphere), the only difference between the two lines is that one using polymer as quench media and another oil. the porocity...
i heard the rule of thumb in heat treatment is that one hour per inch. I assume this is meant to be through hardening. is there any rule of thumb for case hardening?
answer to metengr:
we send the part to a metallurgic lab. I think they did general material test. but i can verify with the lab again.
questions to arunmrao:
what is P/M parts? what is DP test?
thanks,
yush
the job description:
the material is steel 1010, parts are 1 1/4 inch washer. heating 1 hour at 1650F in carbonitride atomsphere. then quench in 90F poplymer. without tempering.
the test on the parts after heat treating shows porosity under the surface.
the question: why porocity happens? and...
stanislas
all you said makes sense. have you ever done such work? if so, would you mind to share me your working template such as excel worksheet. if you do so, please erase or change all confidential data.
thanks,
yush
I were just assigned to do cost analysis in a commercial heat treating company. I am new to this industry. In my previous work, I used to start cost accounting by analyzing Bill of Materials. but this company does not have such thing (BOM). So may be I need to develop one for each of their job...
