Table 5-2  Characteristics of Mold Materials

Material AISI Hardness
HRC 		Wear
resistance 		Corrosion
resistance 		Strength Machinability Surface
finish 		Texture
processability 		Hardenability Weldability
Carbon steel for
machine structural use		 1045-1055 15-20 C D C A++ C B C A
Stainless steel 304   A B            
440C 55-60 A A- A B A- B B C
Carbon tool steel W1-10 63< B- C            
High speed tool steel M2 correspond 63 A+ B A+ B A   B- C
Alloy tool steel O1 60< B- C            
D2 63-65 A B- A B A- A- A C
A2 65 A B A          
H13 45-50 B+ C- A- B+ A A A A-
Precipitation hardened
stainless steel		 S17400 40 B+ A B+ C A B A A
Vacuum-melted
stainless steel		 420 52 A A A B A++   A  
Prehardened steel P21 40 B C- B+ A+ A+ A A A
P20 35 B- C- B A+ A A A A
Copper-beryllium
alloy		 C82800 (UNS num.) 42-48                
C82500 (UNS num.) 35-42                
Evaluation ranks:
  A (superior) > B > C > D (inferior)
  Within a rank: ++ (superior) > + > No sign > - (inferior)