Summary for 316hq stainless steel Discussion
316HQ stainless steel is discussed as a likely misreading or nonstandard designation rather than a widely recognized AISI grade. Bill Reynolds says there is no grade 316HQ and suggests the question may actually refer to 316HC; he also notes that the 316 family does not normally contain copper, except possibly trace residuals around 0.2% at most. Steve Bizub adds that HQ can mean "heading quality," used for special stainless rod or wire intended for cold heading applications, and suggests it may have been a discontinued Carpenter Technology grade. A later reply explains that suffixes on AISI grades usually indicate chemistry variations such as 316H, 316L, 316N, or 316LN, and warns that using suffixes for mechanical-property meanings can be confusing. The thread’s practical takeaway is to verify the exact designation and standard before assuming copper content or a formal 316HQ specification.
Q. Dear Sir/Madam
I am struggling with letters specifications stainless steel type 316HQ. What does “HQ” MEAN? And how many percent by weight of copper is contained? Which standard should I refer to?
HENRY SU
STUDENT – TAINAN COUNTY, TAIWAN
2006
2006
A. I believe there is no grade 316HQ. Perhaps it is a misreading of 316HC?
None of the variations on the 316 theme contains copper (except perhaps occasionally as an accidental residual and unlikely to exceed about 0.2%).
Bill Reynolds [deceased]
consultant metallurgist – Ballarat, Victoria, Australia
We sadly relate the news that Bill passed away on Jan. 29, 2010.
A. Good afternoon:
I’ve never heard of 316HQ, but I have heard of 302HQ, which has a small amount of copper added for improved cold formability. Are you sure that’s not the grade you are looking for?
Steve Bizub
– St Louis, Missouri
2006
2006
A. After reading Steve’s post, I googled 316HQ. 19 hits. The only one in English is the original posting on this thread.
The grade obviously does exist, and one summary suggests that it has copper and selenium as its main claim to fame.
A Chinese site refers to Custom Flo 316HQ and quotes the chemistry as
0.03 C max (which is strange in itself, as in that context “H” usually denotes closer to 0.08 C),
1.0 Si max,
2.0 Mn max,
17.0-19.0 Cr,
8.00-10.0 Ni,
3.00-4.00 Cu and makes no mention of Se.
Live and learn!
Bill Reynolds [deceased]
consultant metallurgist – Ballarat, Victoria, Australia
We sadly relate the news that Bill passed away on Jan. 29, 2010.
A. Interesting information…I wonder if it’s not a discontinued grade from Carpenter Technology.
Forgot to mention earlier that HQ refers to heading quality. This is a special grade of stainless rod or wire for cold heading applications.
Steve Bizub
– St Louis, Missouri
2006
A. Ha! The bits of information start to mesh! letter suffixes to AISI grades usually only refer to variations or tighter ranges on the chemistry spec.
Examples are 316H (carbon high); 316L (carbon low); 316N (significant nitrogen content); 316LN (carbon low plus a significant nitrogen content). And so on for the many dozens of AISI grades of plain carbon and low alloy steels as well as high alloys such as stainless.
When HQ is used in the sense that Steve explains, referring to mechanical properties although the AISI numbers only specify chemistry, it starts a potentially messy trend, fraught with risk of misinterpretation.
However, the original poster of this question at least now has his explanation!
Bill Reynolds [deceased]
consultant metallurgist – Ballarat, Victoria, Australia
We sadly relate the news that Bill passed away on Jan. 29, 2010.
2006
A. Hi Guys
The grade exists and is used frequently on threaded products.
BUT the supplier does not address it, they just name it 316
So the Chinese reference may be the only good reference … Thanks
Steve Hulsey
Steve Hulsey
Metallurgical – BAYTOWN TEXAS USA
May 1, 2019