Stainless Steel E320 PWHT-SA
Heat-treated state
EN E320 · UNS W88021
PWHT-SA = solution annealed after welding
Use when the fabricated component is solution annealed to homogenize the deposit and restore maximum acid resistance in severe sulfuric-acid service.
Values for the PWHT-SA condition
Other E320 tempers and conditions
E320 is listed in 3 conditions; see the grade overview at E320.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
PWHT-SAThis page Solution annealed after welding | Use when the fabricated component is solution annealed to homogenize the deposit and restore maximum acid resistance in severe sulfuric-acid service. | 300 | 560 | 45 | 150 HB | 1.6 % IACS |
As Welded | Choose for TIG root passes, automated GMAW/SAW and thin-wall acid piping where slag-free, cleaner deposits are needed. | 385 | 600 | 38 | 170 HB | 1.6 % IACS |
AW-SMAWDefault As Welded | Standard stocked form: covered stick electrode for field and shop welding of Alloy 20 vessels and acid piping. | 400 | 610 | 35 | 180 HB | 1.6 % IACS |
What is E320 PWHT-SA?
E320 PWHT-SA is E320 heat treated to PWHT-SA — use when the fabricated component is solution annealed to homogenize the deposit and restore maximum acid resistance in severe sulfuric-acid service. E320 PWHT-SA has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 68% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 193 GPa (28 Msi). E320 PWHT-SA has a density of 8.08 g/cm³ (0.292 lb/in³), heavier than 99% of stainless steel grades. It melts at 1,370°C (2,498 °F). AW-SMAW is the default condition FabDigit quotes; PWHT-SA is available on request or by drawing note.
Advantages
- Good corrosion resistance — 84/100, better than 91% of stainless steel grades
- Forms and bends easily — 70/100, better than 79% of stainless steel grades
- Tough — resists crack growth — 190 MPa·√m (172.9 ksi·√in), better than 77% of stainless steel grades
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
Limitations
- Low electrical conductivity — 1.6 % IACS, worse than 99% of stainless steel grades
- High embodied carbon — 7.5 kg CO₂/kg, worse than 97% of stainless steel grades
- Poor heat conductor — 11.8 W/m·K (6.82 BTU/hr·ft·°F), worse than 94% of stainless steel grades
E320 PWHT-SA properties
Typical room-temperature values for E320 PWHT-SA; 23 are specific to this condition. Other listed values are E320 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
E320 PWHT-SA has a density of 8.08 g/cm³ (0.292 lb/in³), heavier than 99% of stainless steel grades. It melts at 1,370°C (2,498 °F).
Mechanical16
E320 PWHT-SA has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 68% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
E320 PWHT-SA is rated for continuous service to 500°C (932 °F). It conducts heat at 11.8 W/m·K (6.82 BTU/hr·ft·°F), worse than 94% of stainless steel grades. Thermal expansion is 14.8 µm/m·K (8.22 µin/in·°F).
Electrical3
E320 PWHT-SA conducts electricity at 1.6 % IACS, worse than 99% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (84/100), better than 91% of stainless steel grades.
Sustainability4
Producing a kilogram of E320 PWHT-SA takes about 95 MJ of energy and emits 7.5 kg of CO₂ — more than 96% of stainless steel grades. Typical recycled content is 40%.
Manufacturability7
E320 PWHT-SA's machinability is poor (28/100, worse than 79% of stainless steel grades); weldability good (60/100); formability very good (70/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with E320 PWHT-SA
Is E320 easy to machine?
Deposits machine like a gummy high-nickel austenitic: slow speeds, heavy positive-rake carbide, rigid setup and flood coolant to avoid work hardening.
Can E320 be welded?
Weld with low heat input, stringer beads (max ~2× electrode dia. weave), interpass below ~150 °C and DCEP; fully austenitic solidification makes it hot-crack sensitive in thick multipass joints — switch to E320LR there.
Can E320 be formed, bent or molded?
Not a wrought product form; deposit itself is ductile (>30 % elongation) and tolerates weld-joint bending and flaring.
What surface finishes work on E320?
Grind out slag and heat tint completely, then pickle (HNO₃-HF) and passivate per ASTM A380/A967 to restore full acid resistance; no anodizing.
E320 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 |
|---|---|---|
| CE320LR variant limits C to 0.035 max | ≤ 0.07 | 0.05 |
| Cr | 19 – 21 | 20 |
| Ni | 32 – 36 | 34 |
| Mo | 2 – 3 | 2.5 |
| Cukey to hot sulfuric acid resistance | 3 – 4 | 3.5 |
| NbNb+Ta, 8×C minimum (stabilization) | ≤ 1 | 0.6 |
| Mn | ≤ 2.5 | 1.8 |
| Si | ≤ 0.6 | 0.4 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Febalance, approx. 35 % | balance | — |
E320 PWHT-SA — frequently asked
What is E320 PWHT-SA used for?
E320 PWHT-SA is typically used for sulfuric acid production equipment, chemical process vessels and alloy 20 fabrication. In short: matching Alloy 20 filler; hot sulfuric acid service; hot-crack sensitive in thick joints.
What is the yield strength of E320 PWHT-SA?
E320 PWHT-SA has a typical yield strength of 300 MPa (43.5 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 68% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is E320 PWHT-SA easy to machine?
Not especially — machinability is rated poor (28/100, worse than 79% of stainless steel grades). Deposits machine like a gummy high-nickel austenitic: slow speeds, heavy positive-rake carbide, rigid setup and flood coolant to avoid work hardening.
Can E320 PWHT-SA be welded?
Yes — weldability is rated good (60/100). Weld with low heat input, stringer beads (max ~2× electrode dia. weave), interpass below ~150 °C and DCEP; fully austenitic solidification makes it hot-crack sensitive in thick multipass joints — switch to E320LR there.
What surface finishes work on E320 PWHT-SA?
Grind out slag and heat tint completely, then pickle (HNO₃-HF) and passivate per ASTM A380/A967 to restore full acid resistance; no anodizing.
Can E320 PWHT-SA be formed, bent or molded?
Not a wrought product form; deposit itself is ductile (>30 % elongation) and tolerates weld-joint bending and flaring.
What is the maximum service temperature of E320 PWHT-SA?
E320 PWHT-SA is rated for continuous use to about 500°C (932 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between E320 AW-SMAW and E320 PWHT-SA?
AW-SMAW is the default condition — standard stocked form: covered stick electrode for field and shop welding of Alloy 20 vessels and acid piping. PWHT-SA: use when the fabricated component is solution annealed to homogenize the deposit and restore maximum acid resistance in severe sulfuric-acid service. Yield strength is 400 MPa in AW-SMAW versus 300 MPa in PWHT-SA.
Sources
- AWS A5.4/A5.4M — Stainless Steel Electrodes for Shielded Metal Arc Welding — American Welding Society (2012)
- AWS A5.9/A5.9M — Bare Stainless Steel Welding Electrodes and Rods — American Welding Society (2017)
- ASTM B463 / B473 — UNS N08020 Alloy Plate, Sheet, Strip and Bar — ASTM International (2020)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering — ASM International (1993)
- Alloy 20 (Carpenter 20Cb-3) technical datasheet — Carpenter Technology (2020)
- Stainless and nickel filler metal catalog (E320 / ER320) — ESAB / Lincoln Electric (2022)
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.