Silicone to Metal Bonding

The technique of bonding silicone or other elastomers to a metal surface has blossomed into a significant portion of our manufacturing schedule. Silicone to metal bonding has resulted in some unique and cost-saving designs. In fact, in cooperation with a manufacturer of high-speed printing systems, we have developed a re-bonding regiment that has significantly reduced their costs related to re-usable service parts.

For qualified elastomers, C & M Rubber Co. will assist your organization in processing the required documents to apply for UL and /or NSF Certification.

Silicone to Metal Bonding Capabilities

Max. Tooling Dimension
24" W x 24"D
Max. Tooling Height
2" to 7" Range
Mold Types
Compression & Transfer
Mold Configuration
Single or Multiple Cavities
Max. Cavity Count
Determining Factors: Part Size & Target Piece Price
Insert Composition
Insert must withstand clamping pressure during molding process
Metal or other thermo-resistant material (400°F)
Bonding Surface Requirements
Degreasing and /or shot blasting of target bonding areas may be necessary for solid adhesion
Free of oil, grease or lubricants
Bonding Methods
Physical encapsulation and/or heat activated adhesive bonding
Bonding Agents
A wide variety of bonding agents are available for a host of application requirements and environmental conditions. Consult with our engineers for best recommendation.
Insert Re-Use & Re-Bonding
With proper rubber removal & surface preparation, some metal substrate components can be recycled for re-bonding.
Elastomer Coating
Silicone is a versatile elastomer that bonds well to metal substrates. It is frequently used in applications requiring UL, NSF or FDA 21CFR177.2600 certification where food contact is common. Other materials such as flourosilicone, urethane, neoprene, millathane, EPDM & natural rubber also are used.
Shrink Factor
Variables such as part size, thickness, length, specific application environment, mold type and elastomer used will influence final shrink percentage used. Consult with our engineers for the recommendation.

Commonly Available Elastomer Materials

Manufactured by Momentive:
  • SE-6035-35 Duro - Blending Base
  • SE-6075-75 Duro - Blending Base
  • SE-6335-30 Duro - Blending Base - High Strength
  • SE-5559-U-57 Duro - Flame Retardent - Color Brown Only
  • Tufel® II Platinum Cure - Various Durometer - Used for Medical Applications
Manufactured by Dow:
  • HS-30-30 Duro High Strength - Use Alone or Blended
  • HS-50-50 Duro High Strength - Use Alone or Blended
  • HS-70-70 Duro High Strength - Use Alone or Blended
  • GP 50-50 Duro Base - For Smooth Shiny Surface Finish
  • NPC 40-40 Duro - No Post Cure Required
  • NPC 80-80 Duro - No Post Cure Required
  • Silastic® 160-60-60 Semiconductive Silicone - Resist 10Ohm/cm
  • Silastic® LCS 755 55 Duro - Low Compression Set
Manufactured Shin-Etsu:
  • SG-135U Base - 35 Duro - General Purpose Base
  • SG-175U Base - 75 Duro - General Purpose Base
Manufactured by Dow:
  • LS-2840-40 Duro Flourosilicone
  • LS-2860-75 Duro Flourosilicone
Neoprene, NBR, EPDM, Millable Urethane & Nitrile
Manufactured by Valley Rubber:
  • Custom Mix to Specific Customer Requirements
Durometer & Color
Durometer and color can be customized to meet your specification. Durometer can range from 10-90 Duro Shore A. (±5 points) Silicone can be color matched whereas flourosilicone, urethane, EPDM and natural rubber are typically available in primary,

General Silicone Characteristics

High-Temperature Resistance
Silicone elastomers outperform organics with proven temperature resistance up to 600°F. Even under extreme heat, these compounds provide superior tensile strength, elongation and abrasion resistance.
Low Temperature
Despite extreme temperatures as low as -100°F, most silicone elastomers retain durometer and modulus. Special grades have brittle points below -150°F and remain serviceable at temperatures as low as -130°F.
Compression Resistance
Silicone elastomers offer incomparable resistance to compression set deformation, even at temperatures as low as -120°F or as high as 500°F.
Electrical Properties
Silicone elastomers provide unequaled electrical properties over a wide range of temperatures. The rival mica in terms of resistance to high-voltage ionization and corona. Plus, they show far less dielectric fatigue than TFE resins or organic elastomers.
Fire Resistance
Underwriters Laboratory Flame Test (UL94) is the standard measure of a material's resistance to burning. This UL test is performed on a test sample 5" x 1.2". A 3/4" Bunsen flame is applied for 10 seconds to a vertically supported sample immersed 3/4" into the flame. The time for burning to cease following the initial 10 second exposure is noted. The flame is applied again for 10 seconds and the time for burning to cease including glowing is noted. A total of 5 samples are tested in this manner. 5 additional samples aged for 7 days at 70°C are also tested in this manner. UL Flame Test Ratings and Results
Rating Required Test Results
94 V-0 5 specimens with 10 flame applications, with none exceeding 10 second flame or 50 second total burn.
94 V-1 5 specimens with 10 flame applications, with none exceeding 30-second flame or 250 second total burn.
94 V-2 Same criteria as for 94 V-1, except some dripping is allowed
94 V-HB 3 specimens none of which has either a burn rate exceeding 3 inches per minute or ceases to burn before reaching reference point.
Smoke Generation
Silicone polymers yield low levels of smoke under normal service or fire conditions.
Radiation Resistance
At room temperature, silicone elastomers outperform TFE resin and conventional fluoroelastomers on exposure to 10/8 roentgens.

Quality Assurance

Commitment to Quality
ISO 9001:2015 Certified
Statistical Process Control
Practice Toyota Production System Tenants
Kodak Contour Projector
ACU-Gage Coordinate Measuring System
Electronic Durometer Tester
Scott Tensile Tester
Rheometer 900 Tester
Leitz/ Wetzler Microscope
Batch Control and Tracking
Custom Manufacturing Software Control
Barcode Order Tracking & Invoicing