Quality Assurance Test Conducted on Prototype Vehicle Brake Drums

Brakes on vehicles are safety items. Their failure could result in fatal accidents. It is therefore necessary that quality control tests are conducted on this vehicle sub system to ensure that individual component parts meet well known specifications for good performance. The sand cast brake drums for in-house developed prototype vehicles were tested for chemical composition using atomic optical emission spectrometer, metallographic structure using a metallurgical microscope, and hardness number using Brinnel hardness tester. They were subjected to X-ray examinations to detect casting defects. Other tests such as dimensional accuracy and balancing are not included in this report.

Results of the chemical analysis show that the undissolved carbon in the matrix is responsible for specimen high hardness number. The X-ray show the presence of some foreign material of less density. The graphite distribution conforms with recommended type for brake drums. Other chemical components are within specified range for brake drums.