有高的強度、韌度和良好的淬透性和抗過熱的穩定性，但白點敏感性高，有回火脆性。焊接性較差，焊前需經高溫預熱，焊后需消除應力，經調質后使用。

化學成分

碳C 0.37~0.44

硅Si 0.17~0.37

錳Mn0.50～0.80

硫S 允許殘余含量≤0.025

磷P 允許殘余含量≤0.025

鉻Cr 0.60～0.90

鎳Ni 1.25～1.65

銅Cu 允許殘余含量≤0.25

鉬Mo0.15～0.25

自由鍛件供應哪家好，就找唐山盛通鍛造有限公司。

It has high strength, toughness, good hardenability and resistance to overheating, but has high white point sensitivity and temper brittleness. Poor weldability, preheating before high temperature, need to eliminate stress after welding, after quenching and tempering.

chemical composition

Carbon C 0.37~0.44

Silicon Si 0.17~0.37

Manganese Mn 0.50~0.80

Sulfur S allows residual content ≤0.025

Phosphorus P allows residual content ≤0.025

Chromium Cr 0.60～0.90

Nickel Ni 1.25~1.65

Copper Cu allows residual content ≤ 0.25

Molybdenum Mo0.15～0.25