TITLE:
Development of Iron Based Brake Friction Material by Hot Powder Preform Forging Technique used for Medium to Heavy Duty Applications
AUTHORS:
Mohammad Asif, K. Chandra, P.S. Misra
KEYWORDS:
Forging, Powder Metallurgy, Friction material, brake pad
JOURNAL NAME:
Journal of Minerals and Materials Characterization and Engineering,
Vol.10 No.3,
March
5,
2011
ABSTRACT: A promising friction material, Iron -based friction material, was prepared by powder
metallurgy (PM) processing utilizing hot powder preform forging (near net-shape).The
preparation of the product and its characterization are presented in this paper. These
products are useful in heavy duty Military Aircraft applications such as AN-32. In order to
eliminate costly environmental control systems to protect products during their high
temperature processing (as is conventionally practiced employing hydrogen gas), the present
investigation relies on carbon (mixed in the brake pad formulation) as reducing agent and
high temperature oxidation resistant glassy coating (separately developed) applied over the
product’s surface after cold compacting. After conducting an initial characterization such as
hardness, density and Pin-on Disc tests, the samples were tested in sub-scale dynamometer
under Rejected Take Off conditions. It was observed that the obtained density in the present
investigation is higher than the reported density obtained by sintering route, and wear is on
the lower side of the range as per the Aeronautical Standards. Optical metallography was
used to investigate the microstructure of friction, interface and backing layer. It was
observed that the distribution of ingredients in matrix was homogeneous. The results also
indicate that the coefficient of friction is more stable, and wear is lower with respect to
temperature rise. .