BS EN ISO 4498:2010 pdf free download.Sintered metal materials, excluding hardmetals — Determination of apparent hardness and microhardness.
ISO 4498:2010 specifies methods of hardness testing of sintered metal materials, excluding hardmetals.
Sintered metal materials generally have a porous structure. Therefore, they can be understood as composite metal/pore materials. That is why this International Standard describes two procedures to determine their hardness:
— Procedure 1 for the macrohardness (this is the apparent hardness);
— Procedure 2 for the microhardness (this is the hardness of the metallic phase only).
Tests in Procedure 1 determine Vickers, Brinell and/or Rockwell macrohardnesses; their acronyms are: HV, HBW and HR. These tests determine the apparent hardness (macrohardness) of the materials because indentations generally include both the solid phase and a number of pores. The usual test forces applied to an indenter are from 10 N to 2 000 N.
The apparent hardness value is often used as an expression of the mechanical strength of the material as a whole; it is usually lower than that of a solid material of the same composition and metallurgical condition. However, this does not imply that the functional characteristics (for example wear resistance) are necessarily inferior to those of an equivalent full-density material.
The apparent hardness is a macrostructural property. It characterizes the material taken as a whole.
The microhardness is a microstructural property used to control chemical composition, heat treatment or surface treatment For these purposes, it is necessary to ensure that hardness test indentations are smal enough not to include any visible pores, but only the solid phase.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 4507, Sintered ferrous materials, carburized or carbonitrided — Determination and verification of
case-hardening depth by a micro-hardness test
ISO 4516, Metallic and other inorganic coatings — Vickers and Knoop microhardness tests
ISO 6506-1, Metallic materials — Brinell hardness test — Part 1: Test method
ISO 6507-1, Metallic materials — Vickers hardness test — Part 1: Test method
ISO 6508-1, Metallic materials — Rockwell hardness test — Part 1: Test method (scales A, B, C, D, E, F, G, H,K,N,T)