Zinc Alloy Kirksite
also Kirksite A
Kirksite (Kirksite A) is a zinc-aluminum-copper casting alloy used for low-cost, quick-turnaround tooling such as die models, stamping dies and fixtures.
Reference datasheet — Kirksite 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 F condition
Kirksite tempers and conditions
Kirksite is supplied in 4 conditions, soft to hard. F is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Stabilized | Use before final machining of precision dies to pre-empt natural-ageing shrinkage and residual-stress movement. | 175 | 210 | 4 | 95 HB | 27 % IACS |
Recycled/re-poured tooling metal | Economical choice for non-critical fixtures and blocks poured from scrapped dies; expect slightly lower and more variable ductility. | 180 | 210 | 2 | 100 HB | 25 % IACS |
FDefault As fabricated | Standard condition for poured tooling blocks and die models machined straight from the casting. | 190 | 227 | 3 | 100 HB | 26 % IACS |
Chill cast | Pick when a finer grain and 10–20 % higher strength/hardness are needed on punch noses and wear faces. | 215 | 260 | 4 | 110 HB | 26 % IACS |
What is Kirksite?
Kirksite (Kirksite A) is a zinc-aluminum-copper casting alloy used for low-cost, quick-turnaround tooling such as die models, stamping dies and fixtures. It is poured directly off a master pattern and supplied as-cast, chill-cast, stabilized or remelted stock, giving roughly 227 MPa tensile, 190 MPa yield, 3 % elongation and 100 HB with a machinability score of 85 — far easier to cut and rework than tool steel. The trade-offs are low ductility, a service ceiling near 100 °C, dimensional drift from slow natural ageing, and limited die life, so it suits prototype and low-volume runs rather than production tooling in steel. Kirksite has a density of 6.7 g/cm³ (0.242 lb/in³), heavier than 57% of zinc alloy grades. It melts at 379°C (714 °F). Kirksite has a yield strength of 190 MPa (27.6 ksi) and a tensile strength of 227 MPa (32.9 ksi) — stronger than 50% of zinc alloy grades. Elongation at break is 3% and the elastic modulus is 96 GPa (13.9 Msi).
What is Kirksite used for?
- prototype stamping dies
- die models
- low-volume production tooling
- jigs and fixtures
Advantages
- Readily welded — 30/100, better than 75% of zinc alloy grades
Limitations
- Limited ductility — 3%, worse than 86% of zinc alloy grades
Kirksite properties
Typical room-temperature values for Kirksite-F; bars are the position among zinc alloy grades.
Physical3
Kirksite has a density of 6.7 g/cm³ (0.242 lb/in³), heavier than 57% of zinc alloy grades. It melts at 379°C (714 °F).
Mechanical14
Kirksite has a yield strength of 190 MPa (27.6 ksi) and a tensile strength of 227 MPa (32.9 ksi) — stronger than 50% of zinc alloy grades. Elongation at break is 3% and the elastic modulus is 96 GPa (13.9 Msi).
Thermal6
Kirksite is rated for continuous service to 100°C (212 °F). It conducts heat at 109 W/m·K (63 BTU/hr·ft·°F), worse than 86% of zinc alloy grades. Thermal expansion is 27.4 µm/m·K (15.2 µin/in·°F).
Electrical3
Kirksite conducts electricity at 26 % IACS, worse than 86% of zinc alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (35/100), worse than 82% of zinc alloy grades.
Sustainability4
Producing a kilogram of Kirksite takes about 53 MJ of energy and emits 3.5 kg of CO₂ — less than 68% of zinc alloy grades. Typical recycled content is 70%.
Manufacturability8
Kirksite's machinability is excellent (85/100, better than 89% of zinc alloy grades); weldability poor (30/100); formability poor (15/100).
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 zinc alloy family
Yield strength against density for every zinc alloy grade FabDigit runs. Kirksite is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Kirksite
Is Kirksite easy to machine?
Cuts very freely with sharp positive-rake carbide or HSS at high speed and light feed; use flood coolant or air blast to avoid smearing, and take a light finishing pass after stabilizing.
Can Kirksite be welded?
No arc welding practice — repair worn or damaged die faces by torch flow-welding with matching zinc alloy filler, or simply cut out and re-pour.
Can Kirksite be formed, bent or molded?
Poured at roughly 430–480 °C into plaster, sand, ceramic or steel moulds directly off a master pattern; allow for ~1.2 % solidification shrinkage plus slow natural ageing contraction.
Kirksite 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 |
|---|---|---|
| Alprimary strengthener; controls fluidity and shrinkage | 3.5 – 4.5 | 4 |
| Curaises strength, hardness and creep resistance | 2.5 – 3.5 | 3 |
| Mgsuppresses intergranular corrosion | 0.02 – 0.1 | 0.05 |
| Feimpurity max | ≤ 0.1 | |
| Pbimpurity max — intergranular corrosion | ≤ 0.01 | |
| Cdimpurity max | ≤ 0 | |
| Snimpurity max | ≤ 0 | |
| Znbalance, from Special High Grade zinc | balance |
What surface finishes work on Kirksite?
Cannot be anodized; hand-stone and polish the working face, then chromate, electroless-nickel plate or paint non-working surfaces for storage protection.
Surface treatments FabDigit runs on zinc alloy 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).
Plating
Equivalent designations
Standards and trade names that resolve to Zinc Alloy Kirksite in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- Kirksite A
How much does Kirksite cost?
Kirksite is a premium-cost zinc alloy ($$$), cheaper than about 51% 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.
Kirksite — frequently asked
What is Kirksite used for?
Kirksite is typically used for prototype stamping dies, die models, low-volume production tooling and jigs and fixtures. In short: fast low-cost prototype tooling; free-machining zinc tooling alloy; remeltable and re-pourable.
What is the yield strength of Kirksite?
Kirksite has a typical yield strength of 190 MPa (27.6 ksi) and a tensile strength of 227 MPa (32.9 ksi) — stronger than 50% of zinc alloy grades. Strength varies by condition: see the 4 listed tempers.
Is Kirksite easy to machine?
Yes — machinability is rated excellent (85/100, better than 89% of zinc alloy grades). Cuts very freely with sharp positive-rake carbide or HSS at high speed and light feed; use flood coolant or air blast to avoid smearing, and take a light finishing pass after stabilizing.
Can Kirksite be welded?
Not readily — weldability is rated poor (30/100). No arc welding practice — repair worn or damaged die faces by torch flow-welding with matching zinc alloy filler, or simply cut out and re-pour.
What surface finishes work on Kirksite?
Cannot be anodized; hand-stone and polish the working face, then chromate, electroless-nickel plate or paint non-working surfaces for storage protection.
Can Kirksite be formed, bent or molded?
Poured at roughly 430–480 °C into plaster, sand, ceramic or steel moulds directly off a master pattern; allow for ~1.2 % solidification shrinkage plus slow natural ageing contraction.
What is the maximum service temperature of Kirksite?
Kirksite is rated for continuous use to about 100°C (212 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Kirksite-F and Kirksite CHILL?
F is the default condition — standard condition for poured tooling blocks and die models machined straight from the casting. CHILL: pick when a finer grain and 10–20 % higher strength/hardness are needed on punch noses and wear faces. Yield strength is 190 MPa in F versus 215 MPa in CHILL.
How much does Kirksite cost?
Kirksite is a premium-cost zinc alloy ($$$), cheaper than about 51% 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
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys (zinc and zinc alloys) — ASM International (1990)
- ASTM B240 — Zinc and Zinc-Aluminum Alloys in Ingot Form for Foundry and Die Castings — ASTM International (2020)
- ASTM B86 — Zinc and Zinc-Aluminum Alloy Foundry and Die Castings — ASTM International (2018)
- Zinc tooling alloy (Kirksite-type) technical data — Eastern Alloys / zinc alloy producers (2020)
- ASM Handbook Vol. 13B — Corrosion: Materials (zinc alloys) — ASM International (2005)
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.