Methods of Steel Casting
Steel casting is a specialized form of casting involving various types of steel. Steel castings are used when cast irons cannot deliver enough strength or shock resistance.
Examples of items that are steel castings include: hydroelectric turbine wheels, forging presses, gears, railroad car frames, valve bodies, pump casings, mining machinery, marine equipment, and engine casings.
Steel castings are categorized into two general groups: carbons steel and alloy steel.
Steel casting alloys
Alloy steel castings are broken down into two categories: low-alloy steels and high-alloy steels.Low-alloy steels contain less than 8% alloying content and high-alloy steels have 8% or more.
This is a table of some steel casting alloys:
Heat resistant steel castings per ASTM A297-1981 | Grade | Nominal alloy composition [%wt] | Tensile strength, minimum | 0.2% Yield strength, minimum | % Elongation in 2 in., minimum |
| ksi | MPa | ksi | MPa |
| HC | 28 Cr | 55 | 380 | - | - | - |
| HD | 28 Cr, 5 Ni | 75 | 515 | 35 | 240 | 8 |
| HF | 19 Cr, 9 Ni | 70 | 485 | 35 | 240 | 25 |
| HH | 25 Cr, 12 Ni | 75 | 515 | 35 | 240 | 10 |
| HI | 28 Cr, 15 Ni | 70 | 485 | 35 | 240 | 10 |
| HK | 25 Cr, 20 Ni | 65 | 450 | 35 | 240 | 10 |
| HL | 29 Cr, 20 Ni | 65 | 450 | 35 | 240 | 10 |
| HN | 20 Cr, 25 Ni | 63 | 435 | - | - | 8 |
| HP | 26 Cr, 35 Ni | 62.5 | 430 | 34 | 235 | 4.5 |
| HT | 15 Cr, 35 Ni | 65 | 450 | - | - | 4 |
| HU | 19 Cr, 39 Ni | 65 | 450 | - | - | 4 |
| HW | 12 Cr, 60 Ni | 60 | 415 | - | - | - |
| HX | 17 Cr, 66 Ni | 60 | 415 | - | - | - |
Corrosion resistant steel castings per ASTM A743-1981a | Grade | Nominal alloy composition [%wt] | Tensile strength, minimum | 0.2% Yield strength, minimum | % Elongation in 2 in., minimum |
| ksi | MPa | ksi | MPa |
| CF-8 | 9 Cr, 9 Ni | 70 | 485 | 30 | 205 | 35 |
| CG-12 | 22 Cr, 12 Ni | 70 | 485 | 28 | 195 | 35 |
| CF-20 | 19 Cr, 9 Ni | 70 | 485 | 30 | 205 | 30 |
| CF-8M | 19 Cr, 10 Ni, with Mo | 70 | 485 | 30 | 205 | 30 |
| CF-8C | 19 Cr, 10 Ni, with Nb | 70 | 485 | 30 | 205 | 30 |
| CF-16 & CF-16Fa | 19 Cr, 9 Ni, free machining | 70 | 485 | 30 | 205 | 25 |
| CH-10 & CH-20 | 25 Cr, 12 Ni | 70 | 485 | 30 | 205 | 30 |
| CK-20 | 25 Cr, 20 Ni | 65 | 450 | 28 | 195 | 30 |
| CE-30 | 29 Cr, 9 Ni | 80 | 550 | 40 | 275 | 10 |
| CA-15 & CA-15M | 12 Cr | 90 | 620 | 65 | 450 | 18 |
| CB-30 | 20 Cr | 65 | 450 | 30 | 205 | - |
| CC-50 | 28 Cr | 55 | 380 | - | - | - |
| CA-40 | 12 Cr | 100 | 690 | 70 | 485 | 15 |
| CF-3 | 19 Cr, 9 Ni | 70 | 485 | 30 | 205 | 35 |
| CF-3M | 19 Cr, 10 Ni, with Mo | 70 | 485 | 30 | 205 | 30 |
| CG6MMN | Cr-Ni-Ma-Mo | 75 | 515 | 35 | 240 | 30 |
| CG-8M | 19 Cr, 11 Ni, with Mo | 75 | 520 | 35 | 240 | 25 |
| CN-7M | 20 Cr, 29 Ni, with Co & Mo | 62 | 425 | 25 | 170 | 35 |
| CN-7MS | 19 Cr, 24 Ni, with Co & Mo | 70 | 485 | 30 | 205 | 35 |
| CW-12M | Ni, Mo & Cr | 72 | 495 | 46 | 315 | 4 |
| CY-40 | Ni, Cr & Fe | 70 | 485 | 28 | 195 | 30 |
| CA-6NM | 12 Cr, 4 Ni | 110 | 775 | 80 | 550 | 15 |
| CD-4MCu | 25 Cr, 5 Ni, 3 Cu, 2 Mo | 100 | 690 | 70 | 485 | 16 |
| CA-6N | 11 Cr, 7 Ni | 140 | 965 | 135 | 930 | 15 |
Tags: castings investment casting steel castings
Categories: Casting | Author: cyuugagi @ 2010-3-4
