The shear and bending fatigue tests are used to determine the effect of variations in material, geometry, surface condition, stress, and so forth, on the fatigue resistance of coated metallic materials subjected to direct stress for up to 10⁷ cycles. These tests may be used as a relative guide to the selection of coated materials for service under condition of repeated stress.

In order that such basic fatigue data be comparable, reproducible, and can be correlated among laboratories, it is essential that uniform fatigue practices be established.

The results of the fatigue test may be used for basic material property design. Actual components should not be tested using these test methods.

1. Scope

1.1 This test method covers the procedure for determining the shear and bending fatigue performance of calcium phosphate coatings and of porous and nonporous metallic coatings and for determining the bending fatigue performance of metallic coatings oversprayed with calcium phosphate. This test method has been established based on plasma-sprayed titanium and plasma-sprayed hydroxylapatite coatings. The efficacy of this test method for other coatings has not been established. In the shear fatigue mode, this test method evaluates the adhesive and cohesive properties of the coating on a metallic substrate. In the bending fatigue mode, this test method evaluates both the adhesion of the coating as well as the effects that the coating may have on the substrate material. These methods are limited to testing in air at ambient temperature. These test methods are not intended for application in fatigue tests of components or devices; however, the test method which most closely replicates the actual loading configuration is preferred.

1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

E6 Terminology Relating to Methods of Mechanical Testing

E206 Definitions of Terms Relating to Fatigue Testing and the Statistical Analysis of Fatigue Data; Replaced by E 1150

E466 Practice for Conducting Force Controlled Constant Amplitude Axial Fatigue Tests of Metallic Materials

E467 Practice for Verification of Constant Amplitude Dynamic Forces in an Axial Fatigue Testing System

E468 Practice for Presentation of Constant Amplitude Fatigue Test Results for Metallic Materials

E1012 Practice for Verification of Testing Frame and Specimen Alignment Under Tensile and Compressive Axial Force Application

Keywords

ceramic coatings; composite coatings; fatigue testing; hydroxylapatite; metallic coatings; plasma-sprayed coatings; porous coatings; tribasic calcium phosphate; Bend testing--surgical materials; Bonding; Coatings (surgical implants); Constant-load-amplitude fatigue crack growth rates; Fatigue--surgical implant materials; Loading tests--surgical materials/applications; Metallic coatings; Performance--medical materials/applications; Porosity--medical/surgical materials; Shear testing--medical materials/applications; Stress; Surface analysis

ICS Code

ICS Number Code 25.220.40 (Metallic coatings)

Citing ASTM Standards

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