I have been investigating Charpy test failures in our steel foundry recently and am evaluating our process. One item of concern is a change that was made a couple years ago to our hot topping. Can someone suggest a test that can be done to validate that the hot topping is still working...
At the moment, we are looking into using chromite to address hot tears in some of our castings. I know that Chromite has a good effect on hot tears. My concern is that we have no way to separate it after casting and an unknown amount will end return into the molding sand. I read in one paper...
Is anyone familiar with whether there are adverse effects of chromite sand getting back into molding sand in steel casting applications. This can be with either green sand or Airset molding?
I am looking for an alternative to buying a different material. We can cast the racks here in a low alloy carbon steel. I am looking for a coating that can be Austenitized in a slightly oxidizing atmosphere and then quenched in water. Basically, my intention is to increase the life of the...
Can anyone suggest where I can find an anti scaling coating that can be applied to steel racks that will be austenitized and quenched in water?
Thank you.
It's an internal alloy that got normalized prior to hardening. The cracks appeared in MPI. There was only some grinding near the crack. Secondary shrink was found after opening the crack to investigate.
I am seeing some castings with quench cracks appearing in areas close to secondary shrink. Does anyone know if there have been studies into whether areas of secondary shrink would increase the potential for a quench crack?
Has anyone ever heard of a quench crack that cannot be seen by wet mag? I am new to my company, and it has been said that these cracks occur after quench and temper, but can only be found if the surface is ground.
We are not seeing the cracks before HT in this case. There are no weld repairs. It is an area we fought hot tears in the past, so we MPI prior to HT. It is a proprietary grade.
The reason I brought this question up is the similarity of a "Fish eye" to a quench crack. This part is having a...
we perform MPI before HT in the areas that we typically see hot tears. The parts go through Normalize and then an AQT. These cracks occur before any weld repair is done.
I am seeing some strange cracking patterns in castings when performing MPI after the quench and temper operation. In some cases they appear similar to HAC. Can anyone suggest a way to differentiate between the two?
