HV30=200 for steel sheet need to be dish end , does high hardness Inconsistent with forming end?

[AhmedDeiaa]

unfortunately,i have a steel 37 sheet with HV30 = 200 (Hardness No.).(this high hardness due to wrong cold rolling).

as you all know that cold working increase the hardness of metal and the material needed to be formed should contain a high amount of ductility so as to easy cold working .

so,can any one tell me what will happen during press and flanging processes of this sheet to obtain a dish end(end cup) of pressure vessel ?

and if it is ok and the hardness HV30 became 270 after forming,is it safe from design point of view ?



some one tell me ,you can heat the sheet during press and flanging process , this heat decrease the hardness and then you will be able to forming the sheet on flanging dish end machine, does it works ?

note:- the dish end required is 3100 mm outer diameter and 14 mm thickness.

 

[metengr]

You have several options. One is to hot work the material and perform heat treatment after forming to establish the required material condition by design.

The second option is to perform a stress relief heat treatment to remove the affects of cold working and restore ductility.

Either,way, the hardness of 270 is too high.