概述
Alloy 88 (Waukesha Metal 88 equivalent, ASTM A494 Grade CY5SnBiM / UNS N26055) is the reference anti-galling alloy for unlubricated metal-on-metal contact. Bismuth and tin, deliberately added at 3–5% each, form low-friction self-lubricating phases inside a nickel-chromium-molybdenum matrix: unlubricated sliding pairs that would seize or gall in 304/316 stainless steel run freely in Alloy 88, galls occurring at roughly one-fifth the rate of 316. That makes it the standard material for rotary pump rotors, bushings and wear parts in food, dairy and pharmaceutical plants, where lubricants are prohibited — it is FDA approved and meets 3-A sanitary standards for direct food contact, and its chromium and molybdenum content gives corrosion resistance broadly matching austenitic stainless against CIP cleaning chemicals (nitric acid excluded). Alloy 88 should be used in the as-cast condition: it cannot be welded or repaired by welding, is not heat treatable, and is limited to roughly 260°C service with properties that degrade at or below freezing. Shanghai Vertex Alloy Co., Ltd supplies Alloy 88 cast round bar (typically 20–250 mm) and near-net-shape castings to drawing, with EN 10204 3.1 mill certificates, gall-testing data on request and flexible MOQ. Waukesha Metal 88 / WM88 is Waukesha Foundry's proprietary designation — Shanghai Vertex Alloy supplies the equivalent ASTM A494 CY5SnBiM grade. Contact Shanghai Vertex Alloy Co., Ltd for latest stock, sizes and pricing.
尺寸范围
- 20–250 mm (typical cast bar)
牌号标准
| 标准体系 | 数值 |
|---|---|
| Grade | Alloy 88 (Waukesha 88 / WM88 equivalent) |
| 🇺🇸 UNS | N26055 |
| Common Trade Names | Alloy 88, Waukesha 88, CY5SnBiM, ILLIUM 8 (equivalent trade references) |
化学成分
| 元素 | 数值 |
|---|---|
| Ni | Bal |
| Fe | 5 |
| Cr | 12.5 |
| Mo | 3 |
| Bi | 4 |
| Sn | 4 |
| Mn | 0.8 |
机械性能
| 性能 | 数值 |
|---|---|
| Tensile Strength | ≈ 330–480 MPa (48–70 ksi) |
| Yield Strength | ≈ 260 MPa (38 ksi) |
| Elongation | ≥ 30% (cast condition) |
| Hardness | 121–170 HB (149 HB typical) |
| Elastic Modulus | 186 GPa (27.0 × 10⁶ psi) |
| Galling Performance | Galls at roughly 1/5 the rate of 316 stainless steel (manufacturer data) |
物理性能
| 性能 | 单位 | 数值 |
|---|---|---|
| Density | - | 8.6 g/cm³ (0.31 lb/in³) |
| Coefficient of Thermal Expansion | - | 8.0 × 10⁻⁶ in/in·°F (0–260°C) — similar to 304 stainless steel |
| Thermal Conductivity | - | Low — 16.7 BTU·in/(hr·ft²·°F) at 105°F, valued for temperature-sensitive areas |
| Electrical Resistivity | - | 112.7 µΩ·cm at 77°F |
| Magnetic Permeability | - | ≈ 10⁻⁴ H/m — essentially non-magnetic, not attracted by a magnet |
| Machinability | - | Comparable to 304 stainless steel |
应用场景
- Food & Beverage: Rotary lobe & positive displacement pump rotors;Unlubricated bushings, wear rings, pump covers
- Dairy:Pump components for CIP-cleaned process lines
- Pharmaceutical:Hygienic pump and valve internals
- Valves:Valve seats, stems and trim requiring anti-seize behaviour
- Polymer Processing:Low-temperature anti-galling screws and dies
- Defense & Marine:Corrosion-resistant unlubricated bearing surfaces
- General Industry:Any close-tolerance metal-on-metal sliding pair without lubrication