Steel 1095 · heat-treated state
Steel 1095 Q&T 650C
Properties of the Q&T 650C condition, compared with the other 1095 tempers.
Softest tempered condition — highest ductility, used where machining after heat treatment is required.
What is 1095 Q&T 650C?
1095 Q&T 650C is 1095 heat treated to Q&T 650C — softest tempered condition — highest ductility, used where machining after heat treatment is required. 1095 Q&T 650C has a yield strength of 552 MPa (80.1 ksi) and a tensile strength of 896 MPa (130 ksi) — stronger than 72% of steel grades. Elongation at break is 21% and the elastic modulus is 205 GPa (29.7 Msi). 1095 Q&T 650C has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). Annealed is the default condition FabDigit quotes; Q&T 650C is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 75/100, better than 94% of steel grades
- High electrical conductivity — 9.6 % IACS, better than 77% of steel grades
Limitations
- Difficult to weld — 15/100, worse than 91% of steel grades
1095 Q&T 650C properties
Typical room-temperature values for 1095 Q&T 650C — 8 properties are specific to this condition; the rest are grade-level values shared by every 1095 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
1095 Q&T 650C has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical15
1095 Q&T 650C has a yield strength of 552 MPa (80.1 ksi) and a tensile strength of 896 MPa (130 ksi) — stronger than 72% of steel grades. Elongation at break is 21% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
1095 Q&T 650C is rated for continuous service to 400°C (752 °F). It conducts heat at 46.7 W/m·K (27 BTU/hr·ft·°F), better than 74% of steel grades. Thermal expansion is 11.4 µm/m·K (6.33 µin/in·°F).
Electrical3
1095 Q&T 650C conducts electricity at 9.6 % IACS, better than 77% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (8/100), worse than 99% of steel grades.
Sustainability4
Producing a kilogram of 1095 Q&T 650C takes about 26 MJ of energy and emits 2 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 30%.
Manufacturability6
1095 Q&T 650C's machinability is fair (45/100, worse than 65% of steel grades); weldability poor (15/100); formability fair (40/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 1095 tempers and conditions
1095 is also supplied in 10 other conditions. The full side-by-side table is on the 1095 overview.
- AnnealedDefaultSoftest supply condition for machining, blanking and subsequent hardening — the usual stock form for bar and knife-blade plate.380 MPa yield · 192 HB
- Hardened & TemperedStandard blade/cutting-edge condition: near-maximum hardness with just enough tempering to relieve quench stresses.1,500 MPa yield · 60 HRC
- Blue Tempered SpringPre-hardened, ready-to-form spring strip for clips, shims, feeler gauges and flat springs — no post heat treatment needed.1,450 MPa yield · 48 HRC
- Q&TGeneral high-strength/spring condition trading some hardness for markedly better toughness than blade temper.790 MPa yield · 48 HRC
- Cold DrawnPick for straight, close-tolerance bar and high-strength wire where no further heat treatment is planned.760 MPa yield · 27 HRC
- Q&T 540CTougher medium-hardness condition for shafts, chisels and impact-loaded high-carbon parts.676 MPa yield · 34 HRC
- Hot RolledLowest-cost mill condition for parts that will be re-heat-treated; hard, scaly surface and coarse pearlite.570 MPa yield · 31 HRC
- Q&T 650CSoftest tempered condition — highest ductility, used where machining after heat treatment is required.552 MPa yield · 27 HRC
- NormalizedUse to homogenize forgings and refine grain before hardening; fine pearlite gives higher strength than annealed.500 MPa yield · 31 HRC
- SpheroidizedChoose for maximum cold formability/deep drawing of strip and for the best machined finish before hardening.370 MPa yield · 180 HB
Working with 1095 Q&T 650C
Is 1095 easy to machine?
Machine in the annealed or spheroidized state with sharp carbide/HSS tools and generous coolant; hardened 1095 above ~50 HRC needs grinding or EDM.
Can 1095 be welded?
Poor weldability (CE ≈ 1.0) — expect martensite and cracking; if unavoidable, preheat 260–320 °C, use low-hydrogen or austenitic filler and temper immediately after.
Can 1095 be formed, bent or molded?
Cold form only in annealed/spheroidized condition with generous bend radii; hot forge 900–1150 °C and always slow-cool or anneal to avoid quench cracks.
What surface finishes work on 1095?
No inherent corrosion resistance — protect with oil, bluing/black oxide, phosphate, zinc plating or paint; takes a fine polish and holds a sharp ground edge.
1095 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 |
|---|---|---|
| CSAE J403 / ASTM A29 | 0.9 – 1.03 | 0.96 |
| Mn | 0.3 – 0.5 | 0.4 |
| Sitypical for killed steel; not specified in SAE J403 | 0.15 – 0.35 | 0.25 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.05 | 0.02 |
| Fe | balance | — |
1095 Q&T 650C — frequently asked
What is 1095 Q&T 650C used for?
1095 Q&T 650C is typically used for spring clips, blades and cutting tools. In short: maximum hardness spring steel.
What is the yield strength of 1095 Q&T 650C?
1095 Q&T 650C has a typical yield strength of 552 MPa (80.1 ksi) and a tensile strength of 896 MPa (130 ksi) — stronger than 72% of steel grades. Strength varies by condition: see the 11 listed tempers.
Is 1095 Q&T 650C easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 65% of steel grades). Machine in the annealed or spheroidized state with sharp carbide/HSS tools and generous coolant; hardened 1095 above ~50 HRC needs grinding or EDM.
Can 1095 Q&T 650C be welded?
Not readily — weldability is rated poor (15/100). Poor weldability (CE ≈ 1.0) — expect martensite and cracking; if unavoidable, preheat 260–320 °C, use low-hydrogen or austenitic filler and temper immediately after.
What surface finishes work on 1095 Q&T 650C?
No inherent corrosion resistance — protect with oil, bluing/black oxide, phosphate, zinc plating or paint; takes a fine polish and holds a sharp ground edge.
Can 1095 Q&T 650C be formed, bent or molded?
Cold form only in annealed/spheroidized condition with generous bend radii; hot forge 900–1150 °C and always slow-cool or anneal to avoid quench cracks.
What is the maximum service temperature of 1095 Q&T 650C?
1095 Q&T 650C is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in 1095 Q&T 650C?
Yes — 1095 Q&T 650C is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- SAE J403 – Chemical Compositions of SAE Carbon Steels — SAE International (2014)
- ASTM A29/A29M – Steel Bars, Carbon and Alloy, Hot-Wrought — ASTM (2020)
- ASTM A684 – High-Carbon Cold-Rolled Steel Strip — ASTM (2021)
- 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)
- GB/T 699 / GB/T 1298 (T10A) — SAC (2015)
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.