Good morning!!
It is Yolanda , Han ling ‘s colleague, she is out of office, so I instead of her to contact with you.
First , so sorry for inconvenience .
Just confirm with our engineer, that the diameter is too small, so if inspect the hardness on diameter directly , it is not exact.
Generally we will make a flat before inspect and will inspect the flat’s hardness, it is exact.
This part we have inspected the samples which was heat treated at the same time , and the hardness is ok.
So if possible, would you please make a flat and check hardness again? Or return the parts to me ,then we can re-inspect, ok?
Any problem, please let me know.