24 July 2021 Mould Steel Bar
20CrMnTi Mould Steel Bar
20CrMnTi is a carburized steel with high level properties. After carburizing and quenching, it has a hard and wear-resistant surface and a tough core. Under the condition of ensuring hardenability, it has high low-temperature impact toughness. Medium weldability, good machinability after normalizing. After surface carburizing and hardening treatment, 20CrMnTi steel has good workability, small processing deformation, and good fatigue resistance. The main uses are for shafts, piston parts and various special parts of automobiles and airplanes. It is used to manufacture important parts with a cross section of <30mm that are subject to high speed, medium or heavy load, impact and friction, such as gears, ring gears, gear shaft crossheads, etc. It is a substitute steel of 18CrMnTi, mainly used for shafts, piston parts and various special parts of automobiles and airplanes. It is also widely used as carburizing parts. In the automobile and tractor industries, it is used to make important carburized parts with a cross-section below 30mm, high speed, medium or heavy load, and impact and friction, such as gears, shafts, ring gears, gear shafts. Sliding bearing main shaft, cross head, claw clutch, worm, etc.
Chemical Composition:
| C(％) | Si(％) | Mn(％) | P(％) | S(％) | Ni(％) | Cu(％) | Ti(％) |
|---|---|---|---|---|---|---|---|
| 0.17～0.23 | 0.17～0.37 | 0.80～1.10 | ≤0.030 | ≤0.030 | ≤0.20 | 0.30 | 0.04～0.10 |
Mechanical Propoerties:
| Yield Strength Rp0.2(MPa) | Tensile Strength Rm(MPa) | Impact Energy Akv(J) | Elongation δ5 (%) | Reduction of Area ψ (%) | Impact toughness value αkv (J/cm2): | Elastic modulus | Poisson's ratio | Thermal conductivity |
|---|---|---|---|---|---|---|---|---|
| ≥835(85) | ≥1080(110) | ≥55 | ≥10 | ≥45 | ≥69(7) | 207GPa | 0.25 | 1.26×10-5 (1/℃) |
Heat treatment specification and metallographic structure:
Heat treatment specification: Quenching: the first time is 880℃, the second time is 870℃, oil cooling; tempering is 200℃, water cooling, air cooling.
Detailed heat treatment specifications and mechanical properties:
Sample blank size/mm: 15
Heat treatment|Quenching|Heating temperature/℃|First quenching: 880
Heat treatment|quenching|heating temperature/℃|second quenching: 870
Heat Treatment|Quenching|Coolant: Oil
Heat treatment|tempering|heating temperature/℃: 200
Heat treatment|tempering|coolant: water, air
Mechanical properties|Tensile strengthσb/MPa|≥: 1080
Mechanical properties|Yield pointσs/MPa|≥: 850
Mechanical properties|Elongation δ5(%)|≥: 10
Mechanical properties|area shrinkage ψ(%)|≥: 45
Mechanical properties|Impact absorption work AKV/J|≥: 55
Hardness in delivery condition HBS|≥: 217
Heat treatment specification and metallographic structure:
Heat treatment specification: Quenching: first time 880℃, second time 870℃, oil cooling; tempering 200℃, water cooling, air cooling;
Metallographic structure: tempered martensite.
Delivery status:
delivery in the heat treatment (normalizing, annealing or high temperature tempering) or non-heat treatment status, the delivery status should be indicated in the contract.
The density and elastic modulus of 20CrMnTi:
Density: 7.8×103kg/m3 Elastic modulus: 207GPa Poisson's ratio: 0.25 Thermal conductivity: 1.26×10-51/℃
20CrMnTi normalizing:
20CrMnTi normalizing, 20CrMnTi steel is heated at 860°C and kept quickly cooled to 680°C and then air-cooled. The high temperature normalizing process is compared with the fog-cooled high-temperature normalizing process after heating at 960°C.