Stainless Steel HL-F (As fabricated)
Temper · default condition
UNS N08604
Standard supply condition for HL furnace hardware — used as cast, no post-cast heat treatment.
Values for the F condition
Other HL tempers and conditions
HL is listed in 3 conditions; see the grade overview at HL.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
FDefaultThis page As fabricated | Standard supply condition for HL furnace hardware — used as cast, no post-cast heat treatment. | 340 | 565 | 15 | 192 HB | 1.8 % IACS |
Centrifugally cast tube/ring | Pick for radiant tubes, rolls and sleeves where the denser, directionally solidified centrifugal structure gives higher soundness and creep life. | 360 | 600 | 17 | 200 HB | 1.8 % IACS |
Service-exposed / thermally aged | Reference condition for repair and life assessment: carbide coarsening and σ-phase drop room-temperature ductility and impact energy sharply. | 380 | 540 | 4 | 220 HB | 1.9 % IACS |
What is HL-F?
HL-F is HL in the F temper — standard supply condition for HL furnace hardware — used as cast, no post-cast heat treatment. HL-F has a yield strength of 340 MPa (49.3 ksi) and a tensile strength of 565 MPa (81.9 ksi) — weaker than 55% of stainless steel grades. Elongation at break is 15% and the elastic modulus is 180 GPa (26.1 Msi). HL-F has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,340°C (2,444 °F).
Advantages
- High service temperature — 1,150°C (2,102 °F), better than 99% of stainless steel grades
Limitations
- Hard to polish — 45/100, worse than 96% of stainless steel grades
- Limited formability — 10/100, worse than 95% of stainless steel grades
- Limited ductility — 15%, worse than 89% of stainless steel grades
- Low electrical conductivity — 1.8 % IACS, worse than 87% of stainless steel grades
- Difficult to weld — 40/100, worse than 83% of stainless steel grades
HL-F properties
Typical room-temperature values for HL-F; 22 are specific to this condition. Other listed values are HL reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
HL-F has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,340°C (2,444 °F).
Mechanical15
HL-F has a yield strength of 340 MPa (49.3 ksi) and a tensile strength of 565 MPa (81.9 ksi) — weaker than 55% of stainless steel grades. Elongation at break is 15% and the elastic modulus is 180 GPa (26.1 Msi).
Thermal6
HL-F is rated for continuous service to 1,150°C (2,102 °F). It conducts heat at 13.5 W/m·K (7.8 BTU/hr·ft·°F), worse than 83% of stainless steel grades. Thermal expansion is 15.5 µm/m·K (8.61 µin/in·°F).
Electrical3
HL-F conducts electricity at 1.8 % IACS, worse than 87% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 52% of stainless steel grades.
Sustainability4
Producing a kilogram of HL-F takes about 62 MJ of energy and emits 4.6 kg of CO₂ — more than 75% of stainless steel grades. Typical recycled content is 70%.
Manufacturability8
HL-F's machinability is poor (28/100, worse than 79% of stainless steel grades); weldability fair (40/100); formability not recommended (10/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with HL-F
Is HL easy to machine?
Machine with rigid setups, sharp carbide or ceramic tooling, low speed/heavy positive feed to cut under the work-hardened skin; grind rather than turn heavily aged material.
Can HL be welded?
Weld with matching HL/high-Cr-Ni or 25-20 (ER310) filler, preheat 150–250 °C, low heat input and slow cooling; service-aged castings should be solution-annealed or buttered before repair welding to avoid hot cracking.
Can HL be formed, bent or molded?
Casting alloy only — sand, investment or centrifugal cast with generous risering and controlled section transitions; no cold forming, hot straightening above 1000 °C only.
What surface finishes work on HL?
Shot blast and pickle/passivate after casting; aluminizing or ceramic coating can extend life in high-sulfur ash, but painting and anodizing are not applicable.
HL 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 |
|---|---|---|
| Chigh C for creep strength | 0.2 – 0.6 | 0.4 |
| Mn | ≤ 2 | 1.2 |
| Siaids scaling resistance | ≤ 2 | 1.5 |
| P | ≤ 0.04 | — |
| S | ≤ 0.04 | — |
| Crhigher than HK for sulfidation/scaling resistance | 28 – 32 | 30 |
| Ni | 18 – 22 | 20 |
| Moresidual only | ≤ 0.5 | — |
| Fe | balance | — |
HL-F — frequently asked
What is HL-F used for?
HL-F is typically used for furnace muffles, heat-treatment fixtures and combustion chamber parts. In short: better scaling than HK; sulfidizing-atmosphere furnace castings; cast-only, no cold forming.
What is the yield strength of HL-F?
HL-F has a typical yield strength of 340 MPa (49.3 ksi) and a tensile strength of 565 MPa (81.9 ksi) — weaker than 55% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is HL-F easy to machine?
Not especially — machinability is rated poor (28/100, worse than 79% of stainless steel grades). Machine with rigid setups, sharp carbide or ceramic tooling, low speed/heavy positive feed to cut under the work-hardened skin; grind rather than turn heavily aged material.
Can HL-F be welded?
With care — weldability is rated fair (40/100). Weld with matching HL/high-Cr-Ni or 25-20 (ER310) filler, preheat 150–250 °C, low heat input and slow cooling; service-aged castings should be solution-annealed or buttered before repair welding to avoid hot cracking.
What surface finishes work on HL-F?
Shot blast and pickle/passivate after casting; aluminizing or ceramic coating can extend life in high-sulfur ash, but painting and anodizing are not applicable.
Can HL-F be formed, bent or molded?
Casting alloy only — sand, investment or centrifugal cast with generous risering and controlled section transitions; no cold forming, hot straightening above 1000 °C only.
What is the maximum service temperature of HL-F?
HL-F is rated for continuous use to about 1,150°C (2,102 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between HL-F and HL Aged?
F is the default condition — standard supply condition for HL furnace hardware — used as cast, no post-cast heat treatment. Aged: reference condition for repair and life assessment: carbide coarsening and σ-phase drop room-temperature ductility and impact energy sharply. Yield strength is 340 MPa in F versus 380 MPa in Aged.
Sources
- ASTM A297/A297M — Steel Castings, Iron-Chromium and Iron-Chromium-Nickel, Heat Resistant, for General Application — ASTM International (2019)
- ASTM A743/A743M — Castings, Iron-Chromium, Iron-Chromium-Nickel, Corrosion Resistant, for General Application — ASTM International (2019)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (Heat-Resistant Castings) — ASM International (1990)
- Steel Castings Handbook, 6th ed. — High Alloy Data Sheets, Heat Series — Steel Founders' Society of America (1995)
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.