This is more of a commercial decision rather than compliance issue. Ultimately the supplier whose name appears on PO is responsible for it. Who does it depends on logistics, cost, and shop capability/certification. I have seen it performed by the last shops, forge shops, outside venders, or...
It is true that (micro)etchants for Ti alloys are quite diluted. However, the #72 makeup you asked about is listed in ASTM E407. The same recipe is also shown in ASTM E340, which is the macroetching standard. You can obtain the Standard copies at ASTM store.
E407 Etchant # 72 is another variant of HF + HNO3 solution.
10 ml HF
45 ml HNO3
45 ml water
You can buy individual chemicals from chemical supply and mix them in fume hood. For metallographic use, HF comes as ~48% conc and HNO3 as ~70% conc.
When dealing with HF, I recommend getting a...
I think 316, even an L grade, is not compatible with chloride environment. Pitting/crevice would be expected. As protective layer breaks down, red rust will be visible.
This is sourcing and inventory issue. Part manufacturers would like flexibility to buy steels from any distributors- small but sufficient quantity at a time. Distributors will have steels certified to A276 most of the times. A276 is widely used whereas F899 is limited to surgical...
There is not any other processing in between annealing and aging. My inquiry came primarily because I heard about potential improvement with cyclic processing and tried to locate the studies.
A secondary reason is due to quality non-conformance issues. Every once in a while there was a cycle...
Thank you all for answers. I am looking into just no more than 5 cycles or so. It wouldn't be economical for us to do too many times.
EdStainless, would you please shed some light on the grain refinement with more cycles? I thought it would cause prior austenite grain growth.
Thank you,
Hello everyone,
I wonder if anyone could point me to articles or studies that determined the effect of multiple annealing+aging cycles on the properties of martensitic PH stainless steel such as 17-4 PH or 13-8 Mo.
Best Regards,
In the investment casting of superalloy such as IN718 and Stellite 21, lower pour temperature gives smaller grain size than higher pour temperature does. Given that the face coat can be zircon and backing is silica, the cooling rate is relatively modest compared to what are achievable by other...
Searching DTIC gave this result. The document was scanned and thus lost some clarity.
http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA020974
Hi experts,
In vacuum heat treating of 17-4 or 13-8, what are common quenching gases? Specifically, would nitrogen cause any concern if used in solution treatment (1900 F) and in aging (H1150 or lower)? For thick section (3-in), is argon adequate or do I need helium?
Thank you,
skaiup
