Steel 50B44
EN 50B44 · UNS G50441
50B44 is a chromium-boron steel (UNS G50441) that delivers deep hardenability similar to plain chromium grades at lower alloy cost.
Reference datasheet — 50B44 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the A condition
50B44 tempers and conditions
50B44 is supplied in 11 conditions, soft to hard. A is the default FabDigit quotes; the values on this page are for it.
Compare all 11 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Pick for cold heading, deep drawing or heavy cold forming of blades and fasteners. | 350 | 600 | 25 | 174 HB | 8 % IACS |
ADefault Solution annealed | Standard stocking condition for machining, cold forming and blanking before hardening. | 380 | 640 | 22 | 187 HB | — |
Hot rolled | Cheapest mill condition for parts that will be re-austenitized and quenched anyway. | 430 | 725 | 16 | 207 HB | — |
Normalized | Uniform fine grain and predictable response before hardening; also used as a supply condition for forgings. | 520 | 840 | 20 | 24 HRC | — |
Cold drawn | Tighter tolerance and better surface for machined shafts and pins; higher strength, lower ductility. | 640 | 760 | 12 | 17 HRC | 8 % IACS |
Q&T 650 °C | Softest quenched-and-tempered condition — maximum ductility and machinability, still through-hardened structure. | 830 | 950 | 20 | 30 HRC | — |
Q&T 540 °C | General machinery condition for shafts, links and high-strength fasteners needing toughness. | 1,100 | 1,210 | 15 | 38 HRC | — |
Q&T 425 °C | Balance of strength and shock resistance for plow shares, mower blades and track components. | 1,380 | 1,500 | 12 | 44 HRC | — |
commercial hardened wear-part condition | The hardness band most agricultural-tool suppliers ship 50B44 strip/blades in; buy this when hardness, not a tempering recipe, is specified. | 1,450 | 1,620 | 11 | 47 HRC | — |
Q&T 315 °C | Standard wear-part condition: still very hard but with usable impact resistance. | 1,580 | 1,790 | 10 | 50 HRC | — |
Q&T 205 °C | Maximum hardness and wear resistance for tillage points and cutting edges; lowest toughness. | 1,650 | 2,000 | 9 | 55 HRC | — |
What is 50B44?
50B44 is a chromium-boron steel (UNS G50441) that delivers deep hardenability similar to plain chromium grades at lower alloy cost. Annealed stock provides 380 MPa yield, 640 MPa tensile and 22 % elongation at 187 HB (90 HRB); tempers on file run from QT205 through QT650 and up to a 45–50 HRC hardened condition, in hot-rolled, annealed, spheroidized, normalized and cold-drawn forms. Weldability is poor because 0.45 % C plus boron raises the carbon equivalent, there is no corrosion resistance, and a formability score of 45 restricts cold work to annealed material. Use 50B46 when higher hardened strength is needed. 50B44 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F). 50B44 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 640 MPa (92.8 ksi) — weaker than 68% of steel grades. Elongation at break is 22% and the elastic modulus is 205 GPa (29.7 Msi).
What is 50B44 used for?
- springs
- high-strength bolts
- wear parts
Advantages
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
50B44 properties
Typical room-temperature values for 50B44-A; bars are the position among steel grades.
Physical3
50B44 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical13
50B44 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 640 MPa (92.8 ksi) — weaker than 68% of steel grades. Elongation at break is 22% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
50B44 is rated for continuous service to 400°C (752 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), better than 57% of steel grades. Thermal expansion is 12.2 µm/m·K (6.78 µin/in·°F).
Electrical3
50B44 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 50B44 takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
50B44's machinability is good (58/100, better than 75% of steel grades); weldability poor (30/100); formability fair (45/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. 50B44 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 50B44
Is 50B44 easy to machine?
Machine in the annealed or spheroidized condition (~62 % of 1212) with carbide at moderate speed; above 45 HRC switch to grinding, CBN or hard turning.
Can 50B44 be welded?
Poor weldability — boron plus 0.45 % C gives high carbon equivalent; use low-hydrogen consumables, 200–300 °C preheat, controlled interpass and immediate temper or post-weld heat treatment.
Can 50B44 be formed, bent or molded?
Cold form, blank, roll or press only in the annealed/spheroidized state; hot forge 1150–1200 °C, finish above 900 °C, then normalize or anneal to restore uniform grain before hardening.
50B44 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 |
|---|---|---|
| C | 0.43 – 0.48 | 0.46 |
| Mn | 0.75 – 1 | 0.88 |
| Si | 0.15 – 0.35 | 0.25 |
| Cr | 0.4 – 0.6 | 0.5 |
| Bhardenability boron; requires Ti/Al to fix nitrogen | 5×10⁻⁴ – 0 | 0 |
| P | ≤ 0.04 | |
| S | ≤ 0.04 | |
| Fe | balance |
What surface finishes work on 50B44?
Austenitize 830–860 °C, quench in oil (thin sections) or water/polymer, temper 175–650 °C; protect with paint, phosphate-and-oil, black oxide or zinc — avoid acid pickling of hardened parts to prevent hydrogen embrittlement.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel 50B44 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- G50441
How much does 50B44 cost?
50B44 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
50B44 — frequently asked
What is 50B44 used for?
50B44 is typically used for springs, high-strength bolts and wear parts. In short: deep hardening, low alloy cost; chromium-boron spring steel; anneal before cold forming.
What is the yield strength of 50B44?
50B44 has a typical yield strength of 380 MPa (55.1 ksi) and a tensile strength of 640 MPa (92.8 ksi) — weaker than 68% of steel grades. Strength varies by condition: see the 11 listed tempers.
Is 50B44 easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% of steel grades). Machine in the annealed or spheroidized condition (~62 % of 1212) with carbide at moderate speed; above 45 HRC switch to grinding, CBN or hard turning.
Can 50B44 be welded?
Not readily — weldability is rated poor (30/100). Poor weldability — boron plus 0.45 % C gives high carbon equivalent; use low-hydrogen consumables, 200–300 °C preheat, controlled interpass and immediate temper or post-weld heat treatment.
What surface finishes work on 50B44?
Austenitize 830–860 °C, quench in oil (thin sections) or water/polymer, temper 175–650 °C; protect with paint, phosphate-and-oil, black oxide or zinc — avoid acid pickling of hardened parts to prevent hydrogen embrittlement.
Can 50B44 be formed, bent or molded?
Cold form, blank, roll or press only in the annealed/spheroidized state; hot forge 1150–1200 °C, finish above 900 °C, then normalize or anneal to restore uniform grain before hardening.
What is the maximum service temperature of 50B44?
50B44 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.
What is the difference between 50B44-A and 50B44-QT205?
A is the default condition — standard stocking condition for machining, cold forming and blanking before hardening. QT205: maximum hardness and wear resistance for tillage points and cutting edges; lowest toughness. Yield strength is 380 MPa in A versus 1,650 MPa in QT205.
How much does 50B44 cost?
50B44 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- SAE J404 — Chemical Compositions of SAE Alloy Steels — SAE International (2021)
- SAE J1268 — Hardenability Bands for Carbon and Alloy H Steels — SAE International (2019)
- ASTM A29/A29M — Steel Bars, Carbon and Alloy, Hot-Wrought — ASTM International (2020)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.4 — Heat Treating (boron steels, hardenability) — ASM International (1991)
- Machinery's Handbook, 31st ed. — Industrial Press (2020)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.