Tensile metal test according to TCVN 197-1: 2014 is specified in the method of testing metal materials and determining mechanical properties at normal temperature. This standard replaces the replacement of TCVN 197: 2002 (ISO 6892: 1998).
TCVN 4398 (ISO 377), TCVN 10600-1 (ISO 7500-1), TCVN 10601 (ISO 9513), ISO 2566-1, ISO 2566-2
Metal material – Testing of extensometers (dilation) for coaxial tensile testing
Principle of tensile test:
The test is carried out at a temperature normally between 10 ° C and 35 ° C, unless otherwise specified. The test carried out under controlled conditions shall be carried out at a temperature of 23 ° C ± 5 ° C.
Testing requires that the specimen be deformed under the force of traction, usually leading to a fracture, to determine one or more mechanical properties specified.
The shape and size of the test piece may be constrained by the shape and dimensions of the metal product used to take the sample.
The test piece is usually machined with a sample from a product or stamping or casting. However, products with uniform cross-sections (shaped products, bars, wires, etc.) and also cast samples (ie for cast iron and nonferrous metal alloys) can be tested without must go through processing.
The cross-section of the test pieces may be round, square, rectangular, annular or in special cases, possibly some other homogeneous cross-section.
For different materials, take and prepare test samples according to the requirements of TCVN 4398: 2001 (ISO 377).
Metal tensile test conditions
– Tensile speed: Unless otherwise specified in the product standard, the speed of pulling shall comply with the requirements below depending on the nature of the material.
– Clamp principle
The test specimen must be kept in a suitable manner such as wedges, lace clips, burrs, etc.
The ends should be fabricated to ensure that the test piece is held so that the force is placed as far as possible. This is particularly important when testing brittle materials or when determining plastic flow stresses (non-proportional elongation) or yield stresses (total elongation) or yield stresses.
The force measuring system of the test machine shall be tested in accordance with ISO 7500-1 and must be level 1 or more accurate.
To determine the plastic limit (plastic extension or total elongation), the extensometer used must comply with ISO 9513, level 1 or more accurately, to the extent relevant. For other properties (with higher extension), it is possible to use ISO 10613 level 2 extensometers (ISO 9513) to the extent relevant.
– The test speed is based on the stress and speed of deformation.
This post is also available in: Tiếng Việt