Nickel Alloy Hastelloy B-4 HF-A
Heat-treated state
UNS N10629
HF-A = hot worked and solution annealed
Heavy sections and forged parts; slightly lower strength and coarser grain than thin annealed product.
Values for the HF-A condition
Other Hastelloy B-4 tempers and conditions
Hastelloy B-4 is listed in 4 conditions; see the grade overview at Hastelloy B-4.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
HF-AThis page Hot worked and solution annealed | Heavy sections and forged parts; slightly lower strength and coarser grain than thin annealed product. | 370 | 780 | 50 | 10 HRC | 1.3 % IACS |
SADefault Solution annealed | Standard supply condition for plate, sheet, bar, pipe and fittings in acid service — maximum corrosion resistance and ductility. | 390 | 810 | 55 | 200 HB | — |
As-welded deposit | Weld metal / weldment properties; B-4's low carbon and Mn/Cr balance allow service in the as-welded condition in most HCl duties. | 430 | 760 | 35 | 210 HB | 1.3 % IACS |
Cold worked | Choose when higher strength or close tolerance and better surface finish are needed and full corrosion performance of annealed material is not critical. | 850 | 1,050 | 20 | 31 HRC | — |
What is Hastelloy B-4 HF-A?
Hastelloy B-4 HF-A is Hastelloy B-4 heat treated to HF-A — heavy sections and forged parts; slightly lower strength and coarser grain than thin annealed product. Hastelloy B-4 HF-A has a yield strength of 370 MPa (53.7 ksi) and a tensile strength of 780 MPa (113 ksi) — weaker than 55% of nickel alloy grades. Elongation at break is 50% and the elastic modulus is 216 GPa (31.3 Msi). Hastelloy B-4 HF-A has a density of 9.2 g/cm³ (0.332 lb/in³), heavier than 95% of nickel alloy grades. It melts at 1,350°C (2,462 °F). SA is the default condition FabDigit quotes; HF-A is available on request or by drawing note.
Advantages
- Ductile — tolerates forming and impact — 50%, better than 88% of nickel alloy grades
Limitations
- High embodied carbon — 16 kg CO₂/kg, worse than 93% of nickel alloy grades
- Limited service temperature — 425°C (797 °F), worse than 90% of nickel alloy grades
Hastelloy B-4 HF-A properties
Typical room-temperature values for Hastelloy B-4 HF-A; 23 are specific to this condition. Other listed values are Hastelloy B-4 reference data and may not represent this condition. Bars are the position among nickel alloy grades.
Physical3
Hastelloy B-4 HF-A has a density of 9.2 g/cm³ (0.332 lb/in³), heavier than 95% of nickel alloy grades. It melts at 1,350°C (2,462 °F).
Mechanical15
Hastelloy B-4 HF-A has a yield strength of 370 MPa (53.7 ksi) and a tensile strength of 780 MPa (113 ksi) — weaker than 55% of nickel alloy grades. Elongation at break is 50% and the elastic modulus is 216 GPa (31.3 Msi).
Thermal6
Hastelloy B-4 HF-A is rated for continuous service to 425°C (797 °F). It conducts heat at 11 W/m·K (6.36 BTU/hr·ft·°F), worse than 60% of nickel alloy grades. Thermal expansion is 10.3 µm/m·K (5.72 µin/in·°F).
Electrical3
Hastelloy B-4 HF-A conducts electricity at 1.3 % IACS, worse than 89% of nickel alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (79/100), better than 58% of nickel alloy grades.
Sustainability4
Producing a kilogram of Hastelloy B-4 HF-A takes about 220 MJ of energy and emits 16 kg of CO₂ — more than 86% of nickel alloy grades. Typical recycled content is 35%.
Manufacturability8
Hastelloy B-4 HF-A's machinability is poor (19/100, worse than 52% of nickel alloy grades); weldability very good (72/100); formability good (58/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Hastelloy B-4 HF-A
Is Hastelloy B-4 easy to machine?
Machine like a tough Ni-Mo alloy: rigid setup, positive-rake sharp carbide, low speed / heavy positive feed to cut under the work-hardened layer, flood coolant, never dwell.
Can Hastelloy B-4 be welded?
GTAW/GMAW with matching B-4 (Ni-Mo) filler, low heat input, interpass <100 °C, no preheat and normally no PWHT; avoid oxidizing-contaminant pickup and keep the weld clean of sulfur/oils.
Can Hastelloy B-4 be formed, bent or molded?
Formable hot (1150–900 °C, then rapid quench) or cold, but the high work-hardening rate needs ~2× the power of stainless and intermediate solution anneals for severe draws.
What surface finishes work on Hastelloy B-4?
Pickle in HF-HNO₃-free (special nickel-alloy) baths or grit blast + light acid clean after annealing; not anodized or plated — mechanically polished or left mill-annealed for acid service.
Hastelloy B-4 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 |
|---|---|---|
| Moprimary alloying element for reducing-acid resistance | 26 – 30 | 28 |
| Crimproves tolerance to oxidizing contaminants | 1 – 3 | 1.5 |
| Fe | 1 – 6 | 3 |
| Mnadded for thermal stability / HAZ behaviour | 1 – 3 | 1.8 |
| Co | ≤ 3 | — |
| Cu | ≤ 0.5 | — |
| Al | ≤ 0.5 | — |
| Sikept very low for corrosion/stability | ≤ 0.1 | 0.03 |
| Cultra-low carbon | ≤ 0.01 | 0.01 |
| P | ≤ 0.03 | — |
| S | ≤ 0.01 | — |
| Nibalance, typically ≥65 % | balance | — |
Hastelloy B-4 HF-A — frequently asked
What is Hastelloy B-4 HF-A used for?
Hastelloy B-4 HF-A is typically used for hydrochloric acid production and handling, sulfuric acid reducing environments, chemical reactor vessels and piping and acetic acid processing. In short: top hydrochloric acid resistance; low-carbon Hastelloy B upgrade; not for oxidizing acids.
What is the yield strength of Hastelloy B-4 HF-A?
Hastelloy B-4 HF-A has a typical yield strength of 370 MPa (53.7 ksi) and a tensile strength of 780 MPa (113 ksi) — weaker than 55% of nickel alloy grades. Strength varies by condition: see the 4 listed tempers.
Is Hastelloy B-4 HF-A easy to machine?
Not especially — machinability is rated poor (19/100, worse than 52% of nickel alloy grades). Machine like a tough Ni-Mo alloy: rigid setup, positive-rake sharp carbide, low speed / heavy positive feed to cut under the work-hardened layer, flood coolant, never dwell.
Can Hastelloy B-4 HF-A be welded?
Yes — weldability is rated very good (72/100). GTAW/GMAW with matching B-4 (Ni-Mo) filler, low heat input, interpass <100 °C, no preheat and normally no PWHT; avoid oxidizing-contaminant pickup and keep the weld clean of sulfur/oils.
What surface finishes work on Hastelloy B-4 HF-A?
Pickle in HF-HNO₃-free (special nickel-alloy) baths or grit blast + light acid clean after annealing; not anodized or plated — mechanically polished or left mill-annealed for acid service.
Can Hastelloy B-4 HF-A be formed, bent or molded?
Formable hot (1150–900 °C, then rapid quench) or cold, but the high work-hardening rate needs ~2× the power of stainless and intermediate solution anneals for severe draws.
What is the maximum service temperature of Hastelloy B-4 HF-A?
Hastelloy B-4 HF-A is rated for continuous use to about 425°C (797 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Hastelloy B-4-SA and Hastelloy B-4-CW?
SA is the default condition — standard supply condition for plate, sheet, bar, pipe and fittings in acid service — maximum corrosion resistance and ductility. CW: choose when higher strength or close tolerance and better surface finish are needed and full corrosion performance of annealed material is not critical. Yield strength is 390 MPa in SA versus 850 MPa in CW.
Sources
- ASTM B333 — Ni-Mo Alloy Plate, Sheet and Strip (UNS N10629) — ASTM International (2018)
- ASTM B335 — Ni-Mo Alloy Rod — ASTM International (2020)
- ASTM B622/B619 — Ni-Mo Alloy Seamless and Welded Pipe & Tube — ASTM International (2020)
- VDM Alloy B-4 / Nicrofer 6928 hMo material data sheet — VDM Metals (2020)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
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.