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Stainless Steel ZG1Cr18Ni9Ti HIP+ST

Heat-treated state

ASTM CF8C

HIP+ST = hot isostatically pressed then solution treated

Specified for pressure-critical or fatigue-loaded castings where internal microporosity must be closed (RT film/UT class 1).

Premium cost $$$

Values for the HIP+ST condition

Other ZG1Cr18Ni9Ti tempers and conditions

ZG1Cr18Ni9Ti is listed in 4 conditions; see the grade overview at ZG1Cr18Ni9Ti.

Compare all 4 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
As fabricated
Lowest-cost condition for non-critical, low-corrosivity parts where carbide networks and residual casting stress are acceptable.24047025165 HB2.3 % IACS
STDefault
Solution annealed
Standard supply condition: maximum ductility, toughness and corrosion resistance for valve bodies, pumps and pressure-containing castings.24550038150 HB—
HIP+STThis page
Hot isostatically pressed then solution treated
Specified for pressure-critical or fatigue-loaded castings where internal microporosity must be closed (RT film/UT class 1).25052045150 HB2.3 % IACS
Solution treated then stabilizing anneal ~870–900 °C
Choose when the casting runs long-term in the 450–850 °C sensitization range or sees severe intergranular attack (nitric acid); the stabilizing anneal at 870–900 °C after solution treatment ties up carbon.25551034155 HB2.3 % IACS

What is ZG1Cr18Ni9Ti HIP+ST?

ZG1Cr18Ni9Ti HIP+ST is ZG1Cr18Ni9Ti heat treated to HIP+ST — specified for pressure-critical or fatigue-loaded castings where internal microporosity must be closed (RT film/UT class 1). ZG1Cr18Ni9Ti HIP+ST has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 91% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 196 GPa (28.4 Msi). ZG1Cr18Ni9Ti HIP+ST has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,400°C (2,552 °F). ST is the default condition FabDigit quotes; HIP+ST is available on request or by drawing note.

Advantages

  • Readily welded — 80/100, better than 80% of stainless steel grades
  • Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades

Limitations

  • Low strength — 250 MPa (36.3 ksi), worse than 91% of stainless steel grades
  • Hard to polish — 60/100, worse than 80% of stainless steel grades

ZG1Cr18Ni9Ti HIP+ST properties

Typical room-temperature values for ZG1Cr18Ni9Ti HIP+ST; 22 are specific to this condition. Other listed values are ZG1Cr18Ni9Ti reference data and may not represent this condition. Bars are the position among stainless steel grades.

Physical3

ZG1Cr18Ni9Ti HIP+ST has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,400°C (2,552 °F).

Density7.75 g/cm³0.28 lb/in³
Melting Point (Solidus)1,400°C2,552 °F
Liquidus Temperature1,450°C2,642 °F

Mechanical16

ZG1Cr18Ni9Ti HIP+ST has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 91% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 196 GPa (28.4 Msi).

Elastic (Young's) Modulus196 GPa28.4 Msi
Shear Modulus75 GPa10.9 Msi
Bulk Modulus145 GPa21 Msi
Poisson's Ratio0.29
Tensile Strength (Ultimate)520 MPa75.4 ksi
Yield Strength (0.2% offset)250 MPa36.3 ksi
Elongation at Break45%
Reduction in Area60%
Compressive Strength255 MPa37 ksi
Shear Strength345 MPa50 ksi
Fatigue Strength (Endurance Limit)230 MPa33.4 ksi
Fracture Toughness (K_IC)180 MPa·√m164 ksi·√in
Charpy V-Notch Impact (RT)100 J73.8 ft·lbf
Hardness, Brinell150 HB
Hardness, Rockwell B80 HRB
Hardness, Vickers158 HV

Thermal6

ZG1Cr18Ni9Ti HIP+ST is rated for continuous service to 800°C (1,472 °F). It conducts heat at 16 W/m·K (9.24 BTU/hr·ft·°F), better than 58% of stainless steel grades. Thermal expansion is 16.5 µm/m·K (9.17 µin/in·°F).

Thermal Conductivity16 W/m·K9.2 BTU/hr·ft·°F
Specific Heat Capacity500 J/kg·K0.12 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)16.5 µm/m·K9.2 µin/in·°F
Latent Heat of Fusion270 J/g116 BTU/lb
Max Service Temperature (continuous)800°C1,472 °F
Min Service Temperature-196°C-321 °F

Electrical3

ZG1Cr18Ni9Ti HIP+ST conducts electricity at 2.3 % IACS, better than 55% of stainless steel grades.

Electrical Conductivity2.3 % IACS
Electrical Resistivity7.5×10⁻⁷ Ω·m29.5 µΩ·in
Magnetic Responseweakly magnetic

Chemical & Environmental3

Corrosion resistance is good (64/100), better than 54% of stainless steel grades.

Galvanic Potential (seawater, vs SCE)-0.05 V
Corrosion ResistanceGood64/100
Chemical Resistance SummaryGood in nitric acid, dilute organic acids, steam and mild atmospheres; Ti stabilization prevents sensitization after welding or 450–850 °C service. Not suitable for hydrochloric acid, hot chlorides (pitting/SCC) or strong reducing acids — use CF8M/CF3M for those.

Sustainability4

Producing a kilogram of ZG1Cr18Ni9Ti HIP+ST takes about 53 MJ of energy and emits 4.5 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 70%.

Embodied Energy (primary production)53 MJ/kg22,786 BTU/lb
Embodied Carbon (primary production)4.5 kg CO₂/kg
Embodied Water130 L/kg15.6 gal/lb
Typical Recycled Content70%

Manufacturability8

ZG1Cr18Ni9Ti HIP+ST's machinability is fair (37/100, better than 57% of stainless steel grades); weldability very good (80/100); formability poor (28/100).

MachinabilityFair37/100
Machinability Rating (AISI 1212 = 100 %)42%
WeldabilityVery good80/100
Formability (cold)Poor28/100
CastabilityVery good70/100
Brazeability / SolderabilityGood55/100
PolishabilityGood60/100
Anodizing Responsen/a — ferrous alloy; use passivation (HNO₃ or citric per ASTM A967) or electropolishing instead

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with ZG1Cr18Ni9Ti HIP+ST

Is ZG1Cr18Ni9Ti easy to machine?

Gummy and work-hardening like 304 — use rigid setups, sharp positive-rake carbide, 60–110 m/min, heavy feed and flood coolant; skin sand/scale must be removed before finishing cuts.

Can ZG1Cr18Ni9Ti be welded?

Readily welded by GTAW/SMAW, but titanium burns out across the arc — use ER347/E347 (Nb-stabilized) or 308L filler; no post-weld anneal required thanks to stabilization.

Can ZG1Cr18Ni9Ti be formed, bent or molded?

Sand or investment cast at 1520–1560 °C with generous risering (≈2.3 % solidification shrinkage) and controlled 5–15 % delta ferrite to avoid hot tearing.

What surface finishes work on ZG1Cr18Ni9Ti?

Grit-blast, pickle in HNO₃/HF then passivate per ASTM A967; electropolish or mechanical polish for hygienic surfaces — no anodizing.

ZG1Cr18Ni9Ti 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.

ElementSpec limit (wt %)Nominal
C≤0.12 % per GB 2100 legacy ZG1Cr18Ni9Ti; ≤0.08 % in CF8C≤ 0.120.08
Si≤ 1.51
Mn≤ 21.2
P≤ 0.040.03
S≤ 0.040.03
Cr17 – 2018.5
Ni8 – 119.5
Ti≥5×C (stabilizer); CF8C uses Nb ≥8×C, ≤1.0 % instead≤ 0.80.5
Moresidual only unless otherwise agreed≤ 0.5—
Febalance—

ZG1Cr18Ni9Ti HIP+ST — frequently asked

What is ZG1Cr18Ni9Ti HIP+ST used for?

ZG1Cr18Ni9Ti HIP+ST is typically used for exhaust and manifold castings, high-temperature valve bodies and welded pressure castings. In short: highest service temperature here; stabilized CF8C equivalent; no post-weld anneal needed.

What is the yield strength of ZG1Cr18Ni9Ti HIP+ST?

ZG1Cr18Ni9Ti HIP+ST has a typical yield strength of 250 MPa (36.3 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 91% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.

Is ZG1Cr18Ni9Ti HIP+ST easy to machine?

Not especially — machinability is rated fair (37/100, better than 57% of stainless steel grades). Gummy and work-hardening like 304 — use rigid setups, sharp positive-rake carbide, 60–110 m/min, heavy feed and flood coolant; skin sand/scale must be removed before finishing cuts.

Can ZG1Cr18Ni9Ti HIP+ST be welded?

Yes — weldability is rated very good (80/100). Readily welded by GTAW/SMAW, but titanium burns out across the arc — use ER347/E347 (Nb-stabilized) or 308L filler; no post-weld anneal required thanks to stabilization.

What surface finishes work on ZG1Cr18Ni9Ti HIP+ST?

Grit-blast, pickle in HNO₃/HF then passivate per ASTM A967; electropolish or mechanical polish for hygienic surfaces — no anodizing.

Can ZG1Cr18Ni9Ti HIP+ST be formed, bent or molded?

Sand or investment cast at 1520–1560 °C with generous risering (≈2.3 % solidification shrinkage) and controlled 5–15 % delta ferrite to avoid hot tearing.

What is the maximum service temperature of ZG1Cr18Ni9Ti HIP+ST?

ZG1Cr18Ni9Ti HIP+ST is rated for continuous use to about 800°C (1,472 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between ZG1Cr18Ni9Ti-ST and ZG1Cr18Ni9Ti-F?

ST is the default condition — standard supply condition: maximum ductility, toughness and corrosion resistance for valve bodies, pumps and pressure-containing castings. F: lowest-cost condition for non-critical, low-corrosivity parts where carbide networks and residual casting stress are acceptable. Yield strength is 245 MPa in ST versus 240 MPa in F.

Sources

  1. GB/T 2100 (incl. legacy GB 2100 ZG1Cr18Ni9Ti) (2017)
  2. ASTM A351/A351M — Castings, Austenitic, for Pressure-Containing Parts (CF8C) — ASTM International (2022)
  3. ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (Cast Stainless Steels) — ASM International (1990)
  4. Steel Castings Handbook, 6th ed. — 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.