列车制动盘温度演变规律试验研究

Experimental Study on Temperature Evolution Law of Train Brake Disc

基于TM-I型缩比惯性试验机,结合红外热像仪,在制动压力0.35~0.80 MPa、制动初速度60~160 km·h~(-1)条件下,以蠕墨铸铁制动盘为参考系,试验研究铝基制动盘的温度演变规律。结果表明:在制动压力0.80 MPa条件下,制动初速度由100 km·h~(-1)增至160 km·h~(-1)时,铝基制动盘峰值温度场由均匀分布转变为多条分离的带状分布,而铸铁制动盘均有宽度约为10 mm的高温带出现;2种制动盘峰值温度均随制动压力和制动初速度的升高而升高,但在制动过程中铝基制动盘的瞬时峰值温度呈“稳步上升”型,在制动后期下降不明显,而铸铁制动盘则为先快速升高,再“锯齿形”爬升,最后有所下降;制动压力为0.65 MPa时,制动初速度由80 km·h~(-1)增至160 km·h~(-1)时,铝基制动盘径向最大温差由31℃增至56℃,最大温度梯度由1~2℃·mm~(-1)增至3~4℃·mm~(-1),而铸铁制动盘最大温差则由139℃增至233℃,最大温度梯度由7~8℃·mm~(-1)增至10~11℃·mm~(-1),均缘于铝基制动盘的硬度低,导热性能好,变形协调能力强,有利于接触面积最大化,促使制动能量均匀分布,从而降低了局部高温区的形成和温差。

Taking vermicular graphite cast iron brake disc as the reference frame,the temperature evolution laws of aluminum-based brake disc was examined in an experimental study with infrared thermal camera under the braking pressure between 0.35-0.80 MPa at the initial braking speed between 60-160 km·h-1 based on the TM-I type scaling inertial braking dynamometer.The results show that when the initial braking speed increases from 100 km·h-1 to 160 km·h-1 under the braking pressure of 0.80 MPa,the peak temperature field of the aluminum-based brake discs changes from a uniform distribution to a multi-strip zonal distribution,whereas a high-temperature band with the width of about 10 mm occurs on all the cast iron brake discs.The peak temperatures of the two brake discs both increase as the braking pressure and the initial braking speed increase.However,during the process of braking,the transient peak temperature of the aluminum-based brake disc presents a steady rise,and does not show an obvious decrease in the later stage of braking;while the transient peak temperature of the cast iron brake disc first rises rapidly,then climbs zigzag,and finally decreases.When the initial braking speed increases from 80 km·h-1 to 160 km·h-1 at the braking pressure of 0.65 MPa,the maximum radial temperature difference of the aluminum-based brake disc increases from 31℃to 56℃and the maximum temperature gradient increases from 1-2℃·mm-1 to 3-4℃·mm-1;whereas those of the cast iron brake discs increase from 139℃to 233℃and from 7-8℃·mm-1 to 10-11℃·mm-1,respectively.This is due to low stiffness,good thermal conductivity and strong deformation compatibility of the aluminum-based brake disc,which is conducive to maximizing the contact area and promoting the uniform distribution of braking energy,thereby reducing the chance of forming local high-temperature zones and reducing temperature difference.