ASTM C1469
Joint Shear Fixture for Advanced Ceramics
ASTM C1469 Shear Fixture – Universal Grip Data Sheet (PDF)
ASTM C1469 measures the shear strength of joints in advanced ceramics at ambient temperature using asymmetric four-point flexure. It is particularly suited to ceramic matrix composites (CMCs) and may also be used for monolithic advanced ceramics. Universal Grip supplies a precision-machined asymmetric four-point shear fixture for this method.
What ASTM C1469 Measures
The test reports the shear strength of a joint, calculated from the failure load and the joint cross-section. Offsetting the inner and outer loading points creates a region of near-pure shear at mid-span, where the joint sits, so failure is driven through the joint rather than the substrate. Specimens are machined from larger joined pieces, which ASTM prefers over butt-joined halves for straightness and uniformity. The method is intended for joints of low to intermediate strength; high-strength joints tend to fracture at the loading points instead.
How the ASTM C1469 Test Works
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Machine bar specimens from the larger joined piece with the joint at mid-length.
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Measure the specimen cross-section at the joint.
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Set the asymmetric loading points so the zero-moment, maximum-shear plane lines up with the joint.
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Load the specimen in force or displacement control at the rate the standard specifies.
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Record the failure load, confirm the fracture ran through the joint and calculate shear strength.
Specimens and Setup
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Machine specimens from larger joined pieces rather than bonding two halves end to end.
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Keep the joint plane square to the specimen axis and centered between the inner loading points.
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Use the specimen geometry and any notch configuration your copy of the standard calls for.
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Check that fractures pass through the joint; failures at loading points are not valid joint shear results.
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Tell us your specimen dimensions and notch geometry so spans can be set to match.
Universal Grip ASTM C1469 Fixture
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Asymmetric four-point loading geometry concentrates shear at the joint centerline
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Uniform, straight-notched and V-notched specimen geometries accommodated
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Hardened, ground rollers and load points for repeatable contact
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10 kN standard capacity; higher capacities on request
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Hardened tool steel with corrosion-resistant finish
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Clevis pin or threaded adapter for electromechanical and servo-hydraulic frames
Applications
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Ceramic matrix composite (CMC) joints
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Brazed and bonded monolithic ceramics
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Aerospace and power-generation hot-section materials
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Joining process development and quality control
Related Standards and Products
Send us your specimen dimensions, notch geometry, capacity and machine connection through our contact page and we will quote an ASTM C1469 joint shear fixture. Request a quote
ASTM C1469 FAQ
Why asymmetric four-point flexure instead of a lap shear test?
Ceramic joints are brittle and hard to grip, and lap shear specimens add peel and bending. Asymmetric four-point flexure produces a near-pure shear zone at mid-span from a simple bar, so the joint can be tested without gripping or bonding tabs.
Can I test high-strength joints?
C1469 is intended for joints of low to intermediate strength relative to the substrate. With very strong joints, fracture tends to start at the loading points rather than in the joint, and the result is not a valid joint shear strength.
Does C1469 apply to monolithic ceramics?
Yes. It is particularly suited to ceramic matrix composites but may also be used for joined monolithic advanced ceramics, such as brazed or bonded parts.
Is C1469 a high-temperature test?
No. The standard covers testing at ambient temperature. High-temperature joint testing needs a different setup and is outside this method.
What capacity do I need?
The standard fixture is rated at 10 kN, which covers typical machined bar specimens on an electromechanical or servo-hydraulic frame. Higher capacities and custom spans are available on request.