ASTM C1358
Compression Test Grips for Ceramic Matrix Composites
Request ASTM C1358 Fixture Specifications
ASTM C1358 measures the monotonic compressive strength of continuous fiber-reinforced advanced ceramics (ceramic matrix composites, or CMCs) using flat specimens with a solid rectangular cross-section at ambient temperature. Because CMCs are stiff and the specimens are thin, the loading train must be very well aligned. Universal Grip builds compression grips and fixtures matched to your specimen geometry and frame.
What ASTM C1358 Measures
The test reports compressive strength, and with strain measurement, compressive modulus and the stress-strain response. CMCs are used in turbine engines, heat shields and brakes, so compressive data supports design allowables and material development. Results are valid only if the specimen fails in the gage section without buckling or excessive bending.
How the ASTM C1358 Test Works
Machine flat rectangular specimens to the geometry in the standard, with tabs where required.
Verify loading train alignment with a strain-gaged alignment specimen.
Mount the specimen in the compression grips so the load is introduced evenly.
Load at the specified rate to failure, recording force and strain.
Check bending and failure location, then calculate compressive strength and modulus.
Specimens and Setup
Alignment is critical: measure percent bending and keep it within the standard's limit.
Use strain gages on opposite faces to detect bending and buckling.
Inspect specimens for machining damage at the edges.
Reject failures at the grips or tabs.
Confirm specimen geometry and rate against your copy of the current standard.
Universal Grip ASTM C1358 Fixture
Compression grips matched to flat CMC specimen geometry
Precision-aligned loading train to limit bending
Hardened gripping or end-loading surfaces
Adjustable for specimen width and thickness
Capacities to suit high-strength CMCs
Clevis pin or threaded adapters for your frame
Applications
Ceramic matrix composite qualification
Turbine and hot-section material development
Brake and friction CMCs
Aerospace research labs
Related Standards and Products
Send us your specimen dimensions, required capacity and machine connection through our contact page and we will quote an ASTM C1358 compression grip. Request a quote
ASTM C1358 FAQ
What materials does C1358 cover?
Continuous fiber-reinforced advanced ceramics, also called ceramic matrix composites (CMCs), tested as flat rectangular specimens at ambient temperature.
Why is alignment so important?
CMC specimens are thin and stiff, so a small misalignment causes bending or buckling and lowers the measured strength. The standard requires alignment checks with a strain-gaged specimen.
Is C1358 a high-temperature test?
No. C1358 covers ambient temperature. Elevated-temperature compression of CMCs is covered by other standards and needs a furnace and high-temperature fixtures.
Can you build to my specimen drawing?
Yes. Send your specimen drawing, expected load and frame connection through our contact page and we will quote a C1358 fixture.