Specialty Silicone Products (SSP) makes spec grade aerospace materials that meet A-A-59588, AMS, MIL-DTL-25988, ASTM E595 and other specifications. Many of our products have been independently tested, and we offer a full Certificate of Analysis (COA) with every batch. Keep reading to learn about our products and contact SSP to request a quote.
A-A-59588 Materials
A-A-59588 is a specification from the U.S. General Services Administration (GSA) that replaced ZZ-R-765, which is still used on some part drawings. Sometimes, A-A-59588 is written as MIL SPEC AA-59588, AA 59588, AA59588, or A A 59588 instead. Regardless of how it’s written, A-A-59588 contains six alphanumeric classes with durometer-based grades.
The table below provides an overview of A-A-59588 designations and includes links to SSP products.
Class | Description | Grade | SSP Material |
1A | Low temperature resistant | 40 | |
50 | |||
60 | |||
70 | |||
1B | Low temperature resistant and low compression set at high temperature | 40 | |
50 | |||
60 | |||
70 | |||
2A | High temperature resistant | 25 | |
40 | |||
50 | |||
60 | |||
70 | |||
80 | |||
2B | High temperature resistance and low compression set | 40 | |
50 | |||
60 | |||
70 | |||
80 | |||
3A | Low temperature, tear and flex resistant | 50 | |
3B | Tear and flex resistant | 60 |
Applications for these materials include aircraft parts like engine mounts, vibration-isolating mounts, and exhaust hangers.
AMS Materials
Aerospace Material Specifications (AMS) from SAE International define properties, performance, and quality requirements for elastomers and other materials used in aerospace applications. The table below describes AMS silicones and provides links to SSP products, where you’ll find additional information such as technical data sheets.
AMS Number | Short Description with Durometer | SSP Product |
AMS3301 | General purpose (35-45) | |
AMS3302 | Heat and weather resistant (45-55) | |
AMS3303 | Heat and weather resistant (55-65) | |
AMS3304 | Heat and weather resistant (65-75) | |
AMS3305J | General purpose (80) | |
AMS3325 | Fuel and oil resistant (55-65) | |
AMS3332 | Extreme low temperature resistant (15-30) | |
AMS3345 | 1000 psi (45-55) |
MIL-DTL-25988 Materials
MIL-DTL-25988 is a U.S. military detail specification that covers fluorosilicone materials for aerospace and defense applications. The current version of this spec, MIL-DTL-25988C, superseded MIL-R-25988B and will be replaced by AMS-R-25988B. In 2022, the Air Force Research Laboratory (AFRL) canceled MIL-DTL-25988D and reverted to MIL-DTL-25988C after determining that Revision D requirements could not be met.
MIL-DTL-25988 categorizes compliant materials according to Type, Class, and Grade.
- Type 1 materials are for O-rings.
- Type 2 materials are for molded parts, sheets, strips, and extruded shapes.
- Class 1 materials are for general-purpose use.
- Class 2 materials are higher-strength elastomers.
- Grades are durometer-based.
The table below describes the MIL-DTL-25988 fluorosilicones that SSP makes.
Type | Class | Grade | SSP Product |
2 | 1 | 40 | |
2 | 1 | 50 | |
2 | 1 | 60 | |
2 | 1 | 70 | |
2 | 1 | 80 | |
2 | 2 | 75 |
ASTM E595 Materials
ASTM E595 is a standard test method developed by ASTM International to evaluate the outgassing properties of materials for use in space applications. It’s based on an earlier NASA test standard and measures Total Mass Loss (TML) and Collected Volatile Condensable Materials (CVCM) when a material is subjected to vacuum pressure and heat.
The table below describes the ASTM E595 low outgassing silicones that SSP makes.
low temperature silicone with space heritage | |
low temperature with EMI shielding | |
40-durometer, flame-retardant silicone with EMI shielding and a UL 94V0 flame rating. Use in place of GORE GS2100. | |
60-durometer, flame-retardant silicone with EMI shielding and a UL 94 V0 flame rating. Use in place of GORE GS5200. |
Ask SSP for Spec Grade Aerospace Materials
Specialty Silicone Products makes spec grade aerospace materials at our ISO 9001:2015 certified facility in Ballston Spa, New York (USA). Along with fabricated products, SSP offers MIL-DTL-83528 Type A, B, C, D, and K materials for EMI gaskets. For traceable elastomers with lower minimum order quantities and shorter lead times, ask SSP.