材料英语证书考试(PEC)-材料试验词汇A AdherenceThe extent to which a coating bonds to a substrate. Adherence Index-Measure of the Adherence of porcelain enamel and ceramic coatings to sheet metal. Alpha Rockwell HardnessIndex of the resistance of a plastic to surface penetration by a specified indenter under specified load applied with a Rockwell Hardness tester. Higher values indicate higher indentation Hardness. Axial StrainThe Strain in the direction that the load is applied, or on the same axis as the applied load. Analogue boardA machine circuit board, which converts analogue signals into digital signal. Anchor PinA steel pin that connects a grip or jig to an eye end Auto ReturnAuto Return, when set to on, causes the crosshead to return automatically to its Zero point at the end of the test. B Bend TestMethod for measuring Ductility of certain materials. There are no standardized terms for reporting bend test results for broad classes of materials; rather, terms associated with bend tests apply to specific forms or types of materials. For example, materials specifications sometimes require that a specimen be bent to a specified inside diameter (ASTM A-360, steel products). A bend test for Ductility of welds is given in ASTM E-190. Results of tests of fiberboard are reported by a description of the failure or photographs. Bending StrengthAlternate term for Flexural Strength. It is most commonly used to describe flexure properties of cast iron and wood products. Bond StrengthStress (tensile load divided by area of bond) required to rupture a bond formed by an adhesive between two metal blocks. Break ElongationThe Elongation of the specimen to the break point. Breaking LoadLoad which causes fracture in a tensile, compression, flexure or Torsion Test. In tensile tests of textiles and yarns, breaking load also is called breaking strength. In tensile tests of thin sheet materials or materials in form of small diameter wire it is difficult to distinguish between breaking load and the maximum load developed, so the latter is considered the breaking load. Breaking StrengthStress required rupturing the specimen. GLOSSARY OF MATERIALS TESTING Bulk Modulus of ElasticityRatio of Stress to change in volume of a material subjected to axial loading. Related to Modulus of Elasticity (E) and Poissons Ratio (r) by the following equation: Bulk Modulus K=E/3(1-2r). Cleavage StrengthTensile load required to cause separation of a 1-in. long metal-to-metal adhesive bond under the conditions set in ASTM D-1062. Climbing Drum Peel TestMethod for determining Peel Resistance of adhesive bond between a relatively flexible and a rigid material. (ASTM D-1781). Coefficient of ElasticityAn alternate term for Modulus of Elasticity. Cohesive StrengthTheoretical Stress that causes fracture in tensile test if material exhibits no plastic deformation. Complex ModulusMeasure of dynamic mechanical properties of a material, taking into account energy dissipated as heat during deformation and Recovery. It is equal to the sum of static modulus of a material and its loss modulus. In the case of shear loading, it is called dynamic modulus. CompressibilityExtent to which a material is compressed in test for compressibility and Recovery of gasket materials. It is usually reported with Recovery. Compressibility and Recovery TestMethod for measuring behavior of gasket materials under short time compressive loading at room temperature. ASTM F-36 outlines a standard procedure. This test is not designed to indicate long term (creep) behavior and should not be confused with the plastometer test. CompressionTypically a direction of force applied to a sample to decrease its height Compression FatigueAbility of rubber to sustain repeated fluctuating compressive loads. (ASTM D-623) Compression setThe extent to which rubber is permanently deformed by a prolonged compressive load (ASTM D-395). Should not be confused with low temperature compression set. Compression testMethod for determining behavior of materials under crushing loads. Specimen is compressed, and deformation at various loads is recorded. Compressive stress and strain are calculated and plotted as a stress-strain diagram which is used to determine elastic limit, proportional limit, yield point, Yield Strength and (for some materials) compressive strength. Standard compression tests are given in ASTM C-773 (high strength ceramics), ASTM E-9 (metals), ASTM E-209 (metals at elevated temperatures) and ASTM D-695 (plastics). Compression-Deflection TestNondestructive method for determining relationship between compressive load and deflection under load for specimen Compressive DeformationExtent to which a material deforms under a Crushing Load. Compressive StrengthMa