Significance and Use

Multiaxial forces often tend to introduce deformation and damage mechanisms that are unique and quite different from those induced under a simple uniaxial loading condition. Since most engineering components are subjected to cyclic multiaxial forces it is necessary to characterize the deformation and fatigue behaviors of materials in this mode. Such a characterization enables reliable prediction of the fatigue lives of many engineering components. Axial-torsional loading is one of several possible types of multiaxial force systems and is essentially a biaxial type of loading. Thin-walled tubular specimens subjected to axial-torsional loading can be used to explore behavior of materials in two of the four quadrants in principal stress or strain spaces. Axial-torsional loading is more convenient than in-plane biaxial loading because the stress state in the thin-walled tubular specimens is constant over the entire test section and is well-known. This practice is useful for generating fatigue life and cyclic deformation data on homogeneous materials under axial, torsional, and combined in- and out-of-phase axial-torsional loading conditions.

1. Scope

1.1 The standard deals with strain-controlled, axial, torsional, and combined in- and out-of-phase axial torsional fatigue testing with thin-walled, circular cross-section, tubular specimens at isothermal, ambient and elevated temperatures. This standard is limited to symmetric, completely-reversed strains (zero mean strains) and axial and torsional waveforms with the same frequency in combined axial-torsional fatigue testing. This standard is also limited to characterization of homogeneous materials with thin-walled tubular specimens and does not cover testing of either large-scale components or structural elements.

1.2 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

E3 Guide for Preparation of Metallographic Specimens

E4 Practices for Force Verification of Testing Machines

E6 Terminology Relating to Methods of Mechanical Testing

E8 Test Methods for Tension Testing of Metallic Materials

E9 Test Methods of Compression Testing of Metallic Materials at Room Temperature

E83 Practice for Verification and Classification of Extensometer Systems

E111 Test Method for Youngs Modulus, Tangent Modulus, and Chord Modulus

E112 Test Methods for Determining Average Grain Size

E143 Test Method for Shear Modulus at Room Temperature

E209 Practice for Compression Tests of Metallic Materials at Elevated Temperatures with Conventional or Rapid Heating Rates and Strain Rates

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

E606 Practice for Strain-Controlled Fatigue Testing

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

E1417 Practice for Liquid Penetrant Testing

E1444 Practice for Magnetic Particle Testing

E1823 Terminology Relating to Fatigue and Fracture Testing

Keywords

axial strain; axial stress; axial-torsional fatigue; in-phase axial-torsional fatigue test; out-of-phase axial-torsional fatigue test; shear strain; shear stress; strain-controlled testing; thin-walled tubular test specimen; Axial fatigue tests; Axial strain; In-phase axial torsional fatigue test; Out-of-phase axial torsional fatigue test; Shear stress; Strain-controlled testing; Thin-walled tubular test specimen;

ICS Code

ICS Number Code 19.060 (Mechanical testing)

DOI: 10.1520/E2207-08

ASTM International is a member of CrossRef.

ASTM E2207