Steel ZG65Mn-SR (Stress relieved)
Heat-treated state
Used after welding repair or rough machining to prevent distortion and quench cracking of large castings.
Values for the SR condition
Other ZG65Mn tempers and conditions
ZG65Mn is listed in 8 conditions; see the grade overview at ZG65Mn.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Pick when the casting must be heavily machined or straightened before final hardening. | 350 | 660 | 14 | 195 HB | — |
As fabricated | Cheapest condition for non-critical wear castings where dimensional stability and toughness are secondary. | 400 | 700 | 6 | 225 HB | — |
SRThis page Stress relieved | Used after welding repair or rough machining to prevent distortion and quench cracking of large castings. | 400 | 720 | 11 | 17 HRC | 8 % IACS |
N+TDefault Normalized and tempered | Standard stocked condition: good balance of strength, hardness and impact toughness for crusher and mining wear castings. | 560 | 880 | 8 | 25 HRC | — |
Normalized | Refines the coarse as-cast dendritic structure and homogenizes properties before tempering or quenching. | 580 | 930 | 7 | 28 HRC | 8 % IACS |
oil quenched and high tempered (820 °C oil + 500–540 °C) | Choose for impact-dominated parts (jaw plates, hammer bodies) needing toughness more than abrasion life. | 830 | 1,030 | 8 | 33 HRC | — |
oil quenched and medium tempered (820 °C oil + 400–450 °C) | Best all-round wear/impact compromise for liners, blow bars, ripper teeth and track shoes. | 1,050 | 1,250 | 5 | 40 HRC | — |
oil/water quenched and low tempered (810–830 °C + 180–250 °C) | Maximum abrasion resistance for thin-section wear plates and screen parts; brittle, avoid heavy impact and sharp notches. | 1,300 | 1,600 | 2 | 50 HRC | — |
What is ZG65Mn-SR?
ZG65Mn-SR is ZG65Mn heat treated to SR — used after welding repair or rough machining to prevent distortion and quench cracking of large castings. ZG65Mn-SR has a yield strength of 400 MPa (58 ksi) and a tensile strength of 720 MPa (104 ksi) — weaker than 60% of steel grades. Elongation at break is 11% and the elastic modulus is 205 GPa (29.7 Msi). ZG65Mn-SR has a density of 7.81 g/cm³ (0.282 lb/in³), lighter than 84% of steel grades. It melts at 1,420°C (2,588 °F). N+T is the default condition FabDigit quotes; SR is available on request or by drawing note.
Advantages
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
Limitations
- Limited formability — 14/100, worse than 90% of steel grades
- Limited ductility — 11%, worse than 89% of steel grades
- Low fracture toughness — 52 MPa·√m (47.3 ksi·√in), worse than 84% of steel grades
- Limited service temperature — 300°C (572 °F), worse than 78% of steel grades
ZG65Mn-SR properties
Typical room-temperature values for ZG65Mn-SR; 23 are specific to this condition. Other listed values are ZG65Mn reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
ZG65Mn-SR has a density of 7.81 g/cm³ (0.282 lb/in³), lighter than 84% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical16
ZG65Mn-SR has a yield strength of 400 MPa (58 ksi) and a tensile strength of 720 MPa (104 ksi) — weaker than 60% of steel grades. Elongation at break is 11% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
ZG65Mn-SR is rated for continuous service to 300°C (572 °F). It conducts heat at 45 W/m·K (26 BTU/hr·ft·°F), better than 66% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
ZG65Mn-SR conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of ZG65Mn-SR takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 70%.
Manufacturability8
ZG65Mn-SR's machinability is fair (44/100, worse than 71% of steel grades); weldability poor (30/100); formability not recommended (14/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ZG65Mn-SR
Is ZG65Mn easy to machine?
Machine in the annealed or normalized+tempered condition with rigid setups and coated carbide (Vc ≈ 60–110 m/min); above 40 HRC switch to CBN/ceramic or finish by grinding.
Can ZG65Mn be welded?
Poor weldability — 0.65 %C gives CE > 0.9; preheat 300–400 °C, use low-hydrogen or austenitic/Mn-steel electrodes, keep interpass hot and stress-relieve at 600–650 °C immediately after.
Can ZG65Mn be formed, bent or molded?
Sand/resin-shell cast with generous risers and 1.9–2.2 % shrink allowance; slow cooling in mould plus immediate normalizing prevents hot tears and coarse dendrites.
What surface finishes work on ZG65Mn?
Shot-blast the casting, then phosphate + paint, zinc-rich primer or oil for storage; hard-facing overlay or induction hardening can be added on high-wear faces. Not anodizable.
ZG65Mn chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Cgrade-defining carbon level | 0.6 – 0.7 | 0.65 |
| Mn | 0.9 – 1.2 | 1.05 |
| Si | 0.2 – 0.5 | 0.35 |
| Pimpurity limit | ≤ 0.04 | — |
| Simpurity limit | ≤ 0.04 | — |
| Crresidual | ≤ 0.3 | — |
| Niresidual | ≤ 0.3 | — |
| Curesidual | ≤ 0.3 | — |
| Moresidual | ≤ 0.15 | — |
| Fe | balance | — |
ZG65Mn-SR — frequently asked
What is ZG65Mn-SR used for?
ZG65Mn-SR is typically used for crusher liners, hammer heads, wear plates and chute liners. In short: wear-resistant spring-steel casting; hardenable to 48–52 HRC; poor weldability.
What is the yield strength of ZG65Mn-SR?
ZG65Mn-SR has a typical yield strength of 400 MPa (58 ksi) and a tensile strength of 720 MPa (104 ksi) — weaker than 60% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is ZG65Mn-SR easy to machine?
Not especially — machinability is rated fair (44/100, worse than 71% of steel grades). Machine in the annealed or normalized+tempered condition with rigid setups and coated carbide (Vc ≈ 60–110 m/min); above 40 HRC switch to CBN/ceramic or finish by grinding.
Can ZG65Mn-SR be welded?
Not readily — weldability is rated poor (30/100). Poor weldability — 0.65 %C gives CE > 0.9; preheat 300–400 °C, use low-hydrogen or austenitic/Mn-steel electrodes, keep interpass hot and stress-relieve at 600–650 °C immediately after.
What surface finishes work on ZG65Mn-SR?
Shot-blast the casting, then phosphate + paint, zinc-rich primer or oil for storage; hard-facing overlay or induction hardening can be added on high-wear faces. Not anodizable.
Can ZG65Mn-SR be formed, bent or molded?
Sand/resin-shell cast with generous risers and 1.9–2.2 % shrink allowance; slow cooling in mould plus immediate normalizing prevents hot tears and coarse dendrites.
What is the maximum service temperature of ZG65Mn-SR?
ZG65Mn-SR is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ZG65Mn N+T and ZG65Mn-A?
N+T is the default condition — standard stocked condition: good balance of strength, hardness and impact toughness for crusher and mining wear castings. A: pick when the casting must be heavily machined or straightened before final hardening. Yield strength is 560 MPa in N+T versus 350 MPa in A.
Sources
- GB/T 1222 (65Mn chemistry reference) — SAC (2016)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.4 — Heat Treating — ASM International (1991)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.