PU Cast
ASTM AU, EU · also Urethane Rubber, Vulkollan
PU Cast is a thermoset polyurethane elastomer (AU/EU, Vulkollan type) cast from a prepolymer and curative, combining rubber elasticity — about 700 % elongation at 12 MPa tensile strength — with abrasion and cut resistance closer to a plastic.
Values for the Shore A 40 condition
PU Cast grades and fills
PU Cast is supplied in 13 conditions, soft to hard. Shore A 40 is the default FabDigit quotes; the values on this page are for it.
- Microcellular
- Shore A 40
- FR V-0
- Shore A 60
- Shore A 70
- Aliphatic
- Polyether
- Shore A 80
- Polyester
- Shore A 90
- Shore A 95
- Shore D 60
- Shore D 75
Compare all 13 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Microcellular / cellular cast PU (foamed elastomer) | Choose for jounce bumpers, spring aids, shoe soles and vibration isolators where low stiffness at low density and high energy absorption are wanted. | 4 | 250 | 12 Shore D | |
Shore A 40Default Soft cast urethane | Pick for soft pads, vibration isolators, gaskets, flexible tooling and skin-friendly grip parts where high elongation matters more than load capacity. | 12 | 700 | 10 Shore D | |
Flame-retardant cast PU | Choose for potting, cable/rail and enclosure parts needing a V-0 rating; fillers reduce elongation and tear strength. | 18 | 350 | 38 Shore D | |
Medium-soft cast urethane | Pick for seals, bumpers, printing/feed rollers and low-load wheels needing a compliant but tougher rubber. | 22 | 650 | 17 Shore D | |
Medium cast urethane | General-purpose workhorse hardness for rollers, drive wheels, wiper blades and dynamic seals combining resilience with good abrasion resistance. | 30 | 600 | 22 Shore D | |
Aliphatic (HDI/H12MDI) light-stable grade | Choose for clear, non-yellowing outdoor or optical parts (lenses, decorative encapsulation, UV-exposed pads); costs 2–4× aromatic grades. | 30 | 450 | 40 Shore D | |
hydrolysis resistant | Choose when parts see hot water, steam, humidity, microbes or low temperatures; slightly lower abrasion/strength than polyester types. | 35 | 550 | 35 Shore D | |
Medium-hard cast urethane | Pick for load-bearing wheels, chute liners, forming pads and stripper plates where higher stiffness is needed but some flex remains. | 36 | 550 | 30 Shore D | |
maximum abrasion & oil resistance | Choose for maximum wear life, cut/tear and oil resistance in dry service; avoid continuous hot-wet or steam exposure (adipate types hydrolyse). | 40 | 500 | 38 Shore D | |
Hard cast urethane | Pick for heavy-duty wheels, mill liners, press pads and abrasion-critical wear parts at high unit loads. | 42 | 500 | 40 Shore D | |
Shore A 95 / Shore D 45 | Pick where near-plastic stiffness plus impact toughness is required: scraper blades, cyclone liners, sheet-metal forming punches. | 45 | 420 | 45 Shore D | |
Rigid cast polyurethane | Pick for structural cast parts, tooling blocks, gears, dies and impact-resistant machine components where a rigid but non-brittle thermoset is wanted. | 50 | 300 | 60 Shore D | |
Hard rigid cast polyurethane / tooling resin | Pick for rigid urethane tooling boards, jigs, master models and hard structural castings replacing filled epoxy. | 60 | 60 | 75 Shore D |
Supply forms, finishes and certifications
Ways PU Cast is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
FDA | FDA / food-contact compliant cast PU | Certification |
What is PU Cast?
PU Cast is a thermoset polyurethane elastomer (AU/EU, Vulkollan type) cast from a prepolymer and curative, combining rubber elasticity — about 700 % elongation at 12 MPa tensile strength — with abrasion and cut resistance closer to a plastic. Hardness spans Shore A 40 to Shore D 75, covering rollers, wheels, wear pads, bushings and vacuum-cast prototype parts, with polyether, polyester, aliphatic, microcellular, FR V-0 and FDA compounds available. Continuous service is limited to about 80 °C, polyester grades hydrolyse in hot water and steam, and strong acids and bases attack it; NBR or cast nylon are the usual alternatives when heat or hydrolysis governs. PU Cast has a density of 1.1 g/cm³ (0.0397 lb/in³), lighter than 66% of polymer grades. Its glass-transition temperature is -50°C (-58 °F). PU Cast has a tensile strength of 12 MPa (1.74 ksi), weaker than 76% of polymer grades. Elongation at break is 700% and the elastic modulus is 0 GPa (2.9×10⁻⁴ Msi).
What is PU Cast used for?
- Drive and conveyor rollers
- Forklift and caster wheels
- Wear pads and scraper blades
- Suspension bushings and spring elements
- Vacuum-cast prototype housings
- Die-cushion and press pads
- Sport equipment components
Advantages
- Ductile — tolerates forming and impact — 700%, better than 96% of polymer grades
- Forms and bends easily — 85/100, better than 81% of polymer grades
Limitations
- Low stiffness — 0 GPa (2.9×10⁻⁴ Msi), worse than 95% of polymer grades
- Difficult to machine — 25/100, worse than 93% of polymer grades
- Hard to polish — 25/100, worse than 90% of polymer grades
- Difficult to weld — 15/100, worse than 78% of polymer grades
PU Cast properties
Typical room-temperature values for PU Cast-Shore A 40; bars are the position among polymer grades.
Physical5
PU Cast has a density of 1.1 g/cm³ (0.0397 lb/in³), lighter than 66% of polymer grades. Its glass-transition temperature is -50°C (-58 °F).
Mechanical12
PU Cast has a tensile strength of 12 MPa (1.74 ksi), weaker than 76% of polymer grades. Elongation at break is 700% and the elastic modulus is 0 GPa (2.9×10⁻⁴ Msi).
Thermal8
PU Cast is rated for continuous service to 80°C (176 °F). It conducts heat at 0.18 W/m·K (0.104 BTU/hr·ft·°F), worse than 73% of polymer grades. Thermal expansion is 200 µm/m·K (111.1 µin/in·°F).
Electrical5
PU Cast is an electrical insulator with a dielectric strength of 20 kV/mm (508 V/mil) and a resistivity of 1×10¹¹ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (78/100), worse than 61% of polymer grades. UV resistance is fair.
Sustainability4
Producing a kilogram of PU Cast takes about 102 MJ of energy and emits 5 kg of CO₂ — less than 55% of polymer grades. Typical recycled content is 0%.
Manufacturability7
PU Cast's machinability is poor (25/100, worse than 93% of polymer grades); weldability poor (15/100); formability excellent (85/100).
Common Calculations4
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 polymer family
Yield strength against density for every polymer grade FabDigit runs. PU Cast is highlighted; hover a dot for its name, or open the interactive family chart.
Working with PU Cast
Is PU Cast easy to machine?
Machinable by turning/grinding with very sharp, high-rake carbide tools, high surface speed and low feed; soft grades (<70A) need chilling, mandrel support or wet grinding to stop smearing and deflection, Shore D grades cut like a tough plastic.
Can PU Cast be welded?
Thermoset — cannot be melt-welded; join by two-part urethane or polyurethane-compatible adhesive, or by casting fresh material against a cleaned, primed cured surface for a chemical bond.
Can PU Cast be formed, bent or molded?
Open or closed-mould gravity casting of a hot (70–90 °C) degassed prepolymer/curative mix into 100–110 °C moulds, demould in 0.5–2 h and post-cure 16 h at 100 °C; centrifugal casting for rollers and metal-insert bonding with primed, grit-blasted cores.
Manufacturability
The process limits FabDigit applies to PU Cast. Every PU Cast part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
Injection molding
| Mold shrinkage | — |
|---|---|
| Wall thickness | — – — |
| Recommended draft | — |
| Pre-drying | — |
PU Cast 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 |
|---|---|---|
| diisocyanate (MDI/TDI/NDI/H12MDI)prepolymer hard segment; aromatic MDI/TDI standard, aliphatic for light stability | 15 – 35 | 25 |
| chain extender / curative (1,4-BDO, HQEEsets hardness and hot strength; MOCA restricted in many markets | 3 – 12 | 7 |
| catalyst, antioxidant, hydrolysis stabil | 0.1 – 3 | 1 |
| filler (talc/silica/ATH/FR) — filled graused in rigid tooling and FR formulations | 0 – 30 | 0 |
| polyol (polyether PTMEG/PPG or polyestersoft segment; determines hydrolysis vs abrasion balance | ≥ 50 (balance) |
What surface finishes work on PU Cast?
Surface quality replicates the mould, so use polished or lacquered tools and mould release; PU can be ground, sanded and flash-trimmed, and painted or printed only with flexible urethane-based coatings after solvent wipe or plasma/primer treatment.
Surface treatments FabDigit runs on polymer 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).
Injection Molding Coating
Metallization / Functional
Equivalent designations
Standards and trade names that resolve to PU Cast in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- AUEU
- Trade names
- Urethane RubberVulkollan
How much does PU Cast cost?
PU Cast is a standard-cost polymer ($$), cheaper than about 62% 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.
PU Cast — frequently asked
What is PU Cast used for?
PU Cast is typically used for drive and conveyor rollers, forklift and caster wheels, wear pads and scraper blades, suspension bushings and spring elements, vacuum-cast prototype housings and die-cushion and press pads. In short: vacuum-cast urethane prototype.
What is the tensile strength of PU Cast?
PU Cast has a typical tensile strength of 12 MPa (1.74 ksi) — weaker than 76% of polymer grades. Strength varies by condition: see the 13 listed tempers.
Is PU Cast easy to machine?
Not especially — machinability is rated poor (25/100, worse than 93% of polymer grades). Machinable by turning/grinding with very sharp, high-rake carbide tools, high surface speed and low feed; soft grades (<70A) need chilling, mandrel support or wet grinding to stop smearing and deflection, Shore D grades cut like a tough plastic.
Can PU Cast be welded?
Not readily — weldability is rated poor (15/100). Thermoset — cannot be melt-welded; join by two-part urethane or polyurethane-compatible adhesive, or by casting fresh material against a cleaned, primed cured surface for a chemical bond.
What surface finishes work on PU Cast?
Surface quality replicates the mould, so use polished or lacquered tools and mould release; PU can be ground, sanded and flash-trimmed, and painted or printed only with flexible urethane-based coatings after solvent wipe or plasma/primer treatment.
Can PU Cast be formed, bent or molded?
Open or closed-mould gravity casting of a hot (70–90 °C) degassed prepolymer/curative mix into 100–110 °C moulds, demould in 0.5–2 h and post-cure 16 h at 100 °C; centrifugal casting for rollers and metal-insert bonding with primed, grit-blasted cores.
What is the maximum service temperature of PU Cast?
PU Cast is rated for continuous use to about 80°C (176 °F), and briefly to 120°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does PU Cast cost?
PU Cast is a standard-cost polymer ($$), cheaper than about 62% 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.
Can FabDigit make parts in PU Cast?
Yes — PU Cast is available for injection molding; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- Adiprene / Vibrathane cast urethane prepolymer datasheets — LANXESS (formerly Chemtura) (2022)
- Cast polyurethane elastomer property charts (rollers, wheels, wear parts) — Gallagher Corporation (2023)
- VytaFlex / Task urethane casting resin technical bulletins — Smooth-On (2023)
- Engineered Materials Handbook Vol. 2: Engineering Plastics — ASM International (1988)
- ASTM D412 / D624 / D2240 / D395 rubber test methods — ASTM (2021)
- GB/T 531.1 / GB/T 528 (2009)
- CES/Granta EduPack polymer & eco property records (PU elastomer) — Ansys Granta (2023)
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.