Materials We Work With

Chicago Flame Hardening processes a wide variety of ferrous materials, including carbon steels, alloy steels, and cast irons. Each material responds differently to heat treatment, and our process is tailored to achieve the desired hardness, wear resistance, and performance characteristics.

Carbon Steels

1020 • 1035 • 1040 • 1045 • 1060

Commonly used for flame hardening due to their ability to achieve increased surface hardness while maintaining a tough core.

Cast & Ductile Irons

Gray Iron • Ductile Iron • Meehanite

Ideal for applications requiring wear-resistant surfaces with good vibration damping and structural stability.

Alloy Steels

4140 • 4150 • 4340 • 52100

Provide enhanced strength and wear resistance. Alloy steels respond well to controlled heat treatment processes for demanding applications.

Hardness Capabilities & Conversion Chart

Achievable hardness depends on material composition, with carbon content being the primary controlling factor.

Chicago Flame Hardening can achieve a wide range of hardness levels depending on the material and application. The chart below provides a general reference for hardness conversions across common measurement scales.

Maximum Attainable Hardness

Steel / Iron Type Rockwell C
1020 Mild Steel 30–35
1035 45–50
1040 50–55
1045 55–60
1060 60–65
1145 55–60
1545 (Speed Treat) 55–60
4140 58–62
4150 60–65
4340 55–60
52100 60–65
8620 40–45
Meehanite GA 55–60
Ductile Iron 55–65
Gray Iron 35–60
A36 40–45

Hardness Conversion Chart

Brinell Rockwell C Shore
682 62 84
653 60 81
627 59 79
601 58 77
578 56 75
555 55 73
534 54 71
514 52 70
495 51 68
477 50 66
461 48 65
444 47 63
429 46 61
415 44 59
401 43 58
388 42 56
375 40 54
363 39 52
352 38 51
341 37 50
331 36 48
321 34 47
311 33 46
302 32 45
293 31 43
285 30 42
277 29 41
269 28 40
262 27 39
255 25 38
248 24 37
241 23 36
235 22 35
229 20 34
223 19 —
217 18 33
212 16 —
207 15 32
197 13 30
187 10 29
179 8 27
170 5 —
163 3 —
156 1 —
149 — —