Figure 1 – Hot and cold fatigue properties of HM1 and 3Cr2W8V
| Grade |
HRC |
Number of cracks |
Total depth of cracks/mm |
Maximum depth of crack/mm |
| HM1 |
45 |
21 |
0.89 |
0.135 |
| 3Cr2W8V |
47.3 |
8 |
0.56 |
1.34 |
** Test conditions: high frequency induction heating, heating temperature 730~740°C, water cooling, heating 12S, cooling 5S, cycle 630 times.
** GB/T 3Cr2W8V steel is similar as DIN 1.2581, AISI H21 steel
Figure 2 - Relationship between quenching temperature and hardness of HM1 steel
| Quenching temperature/°C |
1040 |
1060 |
1080 |
1100 |
1130 |
1150 |
| Hardness/HRC |
51.8 |
53.2 |
54 |
55 |
53.5 |
52.8 |
Mechanical properties:
Figure 3 - Impact toughness after 600°C tempering at different quenching temperatures
| Quenching temperature/°C |
950 |
1000 |
1030 |
1050 |
1060 |
1090 |
1120 |
| Tempering temperature/°C |
600°C x 1.5h x 2 times, air-cooled |
| Ak/(J/cm2) |
longitudinal |
37 |
37 |
37 |
35 |
40 |
33 |
31 |
| crosswise |
/ |
/ |
15 |
25 |
16 |
/ |
/ |
Figure 4 - Impact toughness and fracture toughness at room temperature and high temperature
| Grades |
Hardness (HRC) |
Impact toughness |
Room fracture toughness
KIC(MPa√m)
|
|
Room
20°C
|
300°C |
600°C |
650°C |
700°C |
| HM1 |
48~48.3 |
12.3 |
19.9 |
28.4 |
29.2 |
27.4 |
29.5 |
| 3Cr2W8V |
48.8~49.1 |
13.0 |
21.3 |
25.0 |
27.4 |
26.1 |
32.7 |
Coefficient of thermal conductivity : λ W/(m·K)
| Temperature °C |
100 |
400 |
480 |
570 |
670 |
| λ |
31.8 |
30.9 |
31.8 |
31.8 |
31.8 |
Coefficient of linear expansion : α(mm/(mm·°C))
| Temperature °C |
20~100 |
20~200 |
20~300 |
20~400 |
20~500 |
20~600 |
20~700 |
| Αx 10-6 |
10.40 |
12.80 |
12.90 |
12.80 |
12.70 |
12.30 |
12.70 |
