steel composiion and its heat treatment

These are japanese designations. When comparing Japanese steels to those of other countries, you need to take into account the other non chemical attributes that may be part and parcel of their practice. Internal cleanliness, macroetch, deoxidation and grain refiner etc. Not just the chemistry.

scr440 is a medium carbon chromium only grade. 8620 is a low carbon, triple alloy of nickel chrome and moly. 8640 would be a more suitable substitute.

Chemical Composition Grade SCr440 Standard JIS G4104 Country Japan

Heat Analysis Element Symbol Min. Max. Carbon C 0.38 0.43 Chromium Cr 0.9 1.2 Manganese Mn 0.6 0.85 Phosphorus P 0.03 Silicon Si 0.15 0.35 Sulfur S 0.03

Oil quench.

milo

No idea about S45BC however S45C is a Japanese plain medium carbon steel designation. Same comments as above. Grade S45C Standard JIS G4051 Country Japan Heat Analysis Element Symbol Min. Max. Carbon C 0.42 0.48 Manganese Mn 0.6 0.9 Phosphorus P 0.03 Silicon Si 0.15 0.35 Sulfur S 0.035 This grade and the SCR440 have double the carbon of the 8620 that you inquired about. S45c oil quench. apologize for the wierd formatting, Macbook and safari aren't best match for cr4 and I don't know the html tags needed to make this look like a professional typed it. milo

Thank u milo for all this information u have provided.

reaaly a great help for me.

Regards

Durga Prasad

You're welcome. Welcome to CR4 milo

Normally in this condition you may try the format :

C=0.42/0.48, Mn=0.6/0.8...

_{But better than there=their}

It would have been so easy to google and then see that it is no where equivalent.

Thanks guest, if your format comments were directed to me. I pasted in a table, which was immediately deconstructed upon hitting preview post button, then magically reconstructed upon edit, etc. etc. I should have booted up my windows machine... milo