Admittedly a disc brake plays an important role in the auto part industry since it concerns directly with safety. Therefore the wide range of disc brake has been designed in order to develop its heat ventilation. There are two physical kinds of brakes: front-vented disc brake and backvented disc brake. As a result such difference affects directly to the heat ventilation which is a vital factor of the brake’s capability. The project team recognizes its importance and tries to create the test to find out the temperature diffusion of the disc brake with the hope to evaluate the coefficient of the heat convection varied by the temperature changing in both kinds of brakes under the forced heat convection in the steady condition. However the steady heat conduction and radiation value will not be counted because it is insignificant. The JASO C406: 2000 Standard is adopted as a guideline in the test. The outcome coefficient of heat conduction will be used in the simulation via the Finite Element Method (FEM) in order to study the temperature diffusion and heat ventilation of both kinds of brakes at each temperature level. Consequently the experimental work reveals then the heat convection coefficients of both kinds are unidirectional. The heat convection coefficient of the front-vented disc brake is 4.40 % in average higher than that of the back-vented disc brake. From the simulation the front-vented disc brake can ventilate the heat better than the back-vented disc brake at 3.02 % in average. It can be summarized that the front-vented disc brake has more temperature difference than the backvented disc brake. Hence the front-vented disc brake likely gets more stress from the temperature than the back-vented disc brake and might be damaged during the operation more than the another type.

Nowadays the automotive industry in Thailand has been widely growing. Brake pad is one of the automotive products that play a vital role in automotive industry because it is the most critical seeurity part. Consequently testing products for quality are extremely requested. However the precise equipment and function tests which show the real effects are not available enough and cost a lot. Therefore they cannot response to the deman in the automotive industry development. In this study the frictional test jigs for friction measurement JIS K7125 [5] and the clutch facings for automobiles JIS D4311 [6]. A study of the frictional test emphasizes on the static friction (μs) and kinetic friction (μk) in different condition. There are 3 specimens of brake pad supposted by the industry company. These specimens were tested and the results from the pin-ondisk and those from the friction testing were compared. The results revealed the correspondence of the two-sided results but the pin-on-disk’s friction coefficient is more than the friction testing’s friction coefficient by 19.56%. Moreover the coefficient of friction varies according to the temperature Besides the static friction (μs) is likely more than kinetic friction (μk) and tends to differ considerably under high pressure condition.