ForMatter/Materials/metal/Bearing Bronze (C93200, SAE 660)
mat_bronze_c93200_bearing

Bearing Bronze (C93200, SAE 660)

leaded tin bronze, plain bearing material · SAE 660, UNS C93200, leaded tin bronze, bearing bronze
highlast updated 2026-04-27
metallic 0.00
hue shift +0°

The bronze the world's plain bearings are cast from. Tin gives it strength, lead gives it self-lubrication where the bearing bore meets the shaft. Yellow-warm in color before machining, gray-brown after. The bronze in old machinery's bushings, in lathe slide nuts, in the thrust washers under heavy moving parts.

Leaded tin bronze (83% Cu, 7% Sn, 7% Pb, 3% Zn nominal per UNS C93200). Lead is dispersed as a soft secondary phase that smears across the bearing interface under load, providing emergency self-lubrication. Tensile 240 MPa as-cast, hardness Brinell 65. Sand-cast or continuous-cast standard form. Lead content (7%) places this bronze outside RoHS-compliance pools for many EU end uses.

mechanical

  • tensile_strength_mpa_as_cast240
  • yield_strength_mpa_as_cast125
  • elongation_pct_as_cast20
  • hardness_brinell_as_cast65
  • density_kg_m38930
source: ASTM B505; ASM Handbook

thermal

  • liquidus_c977
  • solidus_c854
  • thermal_conductivity_w_mk72
source: ASM Handbook

Sustainability

  • embodied carbon kg co2e per kg4.8
  • sourceEditorial estimate from ICE / Granta CES EduPack class databases — industry mean, with cradle-to-gate boundary unless otherwise noted. Embodied carbon for any specific product depends on supplier mix, recycled content, and energy grid; verify against a primary source before using these numbers in a sustainability claim.
  • embodied carbon recycled kg co2e per kg1.9
  • recyclabilityhigh — closed-loop with quality preservation; lead content requires segregated scrap stream
  • biodegradableFalse
  • certificationsASTM B505 (continuous cast), SAE J462
visual
warm yellow-brown as cast, machines to a smoother surface than copper or brass and patinates to dark olive over time
tactile
smooth, dense, machinable with the characteristic clean shaving of leaded alloys
weight perception
heavy

PBR starter values

Principled BSDF defaults derived from the sphere metallic finish. Reasonable seed for Blender, Substance, Keyshot, Rhino — tune per material.

# finish:      metallic
albedo        #8c6840
metallic      1.00
roughness     0.25
ior           1.45
transmission  0.00
clearcoat     0.00
sheen         0.00
anisotropic   0.00
copy as JSON 
{
  "albedo": "#8c6840",
  "metallic": 1.0,
  "roughness": 0.25,
  "ior": 1.45,
  "transmission": 0.0,
  "clearcoat": 0.0,
  "sheen": 0.0,
  "anisotropic": 0.0
}
Blender 4.x Python 
# Blender 4.x — Principled BSDF
# Bearing Bronze (C93200, SAE 660) · finish: metallic
import bpy
mat = bpy.data.materials.new(name="mat_bronze_c93200_bearing")
mat.use_nodes = True
bsdf = mat.node_tree.nodes["Principled BSDF"]
bsdf.inputs["Base Color"].default_value         = (0.2623, 0.1384, 0.0513, 1.0)
bsdf.inputs["Metallic"].default_value           = 1.000
bsdf.inputs["Roughness"].default_value          = 0.250
bsdf.inputs["IOR"].default_value                = 1.450
bsdf.inputs["Transmission Weight"].default_value = 0.000
bsdf.inputs["Coat Weight"].default_value        = 0.000
bsdf.inputs["Sheen Weight"].default_value       = 0.000
bsdf.inputs["Anisotropic"].default_value        = 0.000
KeyShot Python (lux) 
# KeyShot 11+ — lux Python API, Generic material
# Bearing Bronze (C93200, SAE 660) · finish: metallic
# Run from Window → Scripting Console
import lux
mat = lux.createMaterial(name="mat_bronze_c93200_bearing", materialType="Generic")
mat.setProperty("diffuse",      (140, 104, 64))   # 8-bit sRGB
mat.setProperty("metallic",     1.000)
mat.setProperty("roughness",    0.250)
mat.setProperty("indexOfRefraction", 1.450)
mat.setProperty("transparency", 0.000)
mat.setProperty("coatingWeight", 0.000)
Substance pbrMetalRough 
{
  "_format": "Substance Designer / Painter \u2014 pbrMetalRough constants",
  "_about": "Bearing Bronze (C93200, SAE 660) \u00b7 finish: metallic",
  "baseColor": {
    "r": 0.2623,
    "g": 0.1384,
    "b": 0.0513
  },
  "metallic": 1.0,
  "roughness": 0.25,
  "ior": 1.45,
  "opacity": 1.0,
  "anisotropyLevel": 0.0,
  "_notes": "Channels listed are the standard Substance pbrMetalRough output. Drop into a Uniform Color node per channel, or as the constant input on a layered stack."
}
glTF 2.0 Metallic-Roughness 
{
  "asset": {
    "version": "2.0",
    "generator": "ForMatter"
  },
  "materials": [
    {
      "name": "mat_bronze_c93200_bearing",
      "pbrMetallicRoughness": {
        "baseColorFactor": [
          0.2623,
          0.1384,
          0.0513,
          1.0
        ],
        "metallicFactor": 1.0,
        "roughnessFactor": 0.25
      },
      "extensions": {
        "KHR_materials_ior": {
          "ior": 1.45
        }
      }
    }
  ]
}
USD Preview Surface 
# USD Preview Surface — UsdShade.MaterialLook prim attributes
# Bearing Bronze (C93200, SAE 660) · finish: metallic
def Material "mat_bronze_c93200_bearing" {
    token outputs:surface.connect = </mat_bronze_c93200_bearing/PreviewSurface.outputs:surface>

    def Shader "PreviewSurface" {
        uniform token info:id = "UsdPreviewSurface"
        color3f inputs:diffuseColor = (0.2623, 0.1384, 0.0513)
        float   inputs:metallic     = 1.000
        float   inputs:roughness    = 0.250
        float   inputs:ior          = 1.450
        float   inputs:opacity      = 1.000
        float   inputs:clearcoat    = 0.000
        token   outputs:surface
    }
}
↓ download glTF material
ProcessCNC Milling · Brazing
Substitutes
Cartridge Brass (C26000)
Copper C11000 (Electrolytic Tough Pitch)

Citations