Study On The Influence Of Pressure And Roughness On The Interface Heat Transfer Performance Of Low Melting Temperature Alloys

In recent years,the intelligent and unpiloted system had become an inevitable trend of marine development.At the same time,high-power electronic components are widely used in various systems of ships,and that is significant to make sure the stable function of high-power electronic components in the case of efficient heat dissipation.Interface thermal contact resistance is an important factor that affects the high-efficiency heat dissipation of high-power equipment such as electronic components.Therefore,it is a crucial part for safe navigation to make interface heat transfer efficiently by reducing thermal contact resistance.Low melting temperature alloys was taken as a thermal interface material because of its excellent heat transfer performance,which leads to a good industrial prospective.For further research,this paper firstly designed a thermal contact resistance measurement bench that based on one-dimensional steady-state thermal contact resistance measurement method,and also the thermal contact resistance calculation method was optimized.Secondly,the influence of pressure and surface roughness on the thermal contact resistance was investigated.Then the low melting temperature alloys was modified by different diameter copper powder,and the heat transfer performance of the interface was investigated.Finally,the influence of the solid-liquid-solid interface thermal contact resistance theory prediction model with factors pressure and roughness was established,and the influence of pressure and roughness on the interfacial heat transfer performance was revealed.Through the above research work,the following main conclusions can be drawn:(1)With the increase of interface contact pressure,the thermal contact resistance shows a downward trend,and gradually stabilizes at around 0.2 MPa.When the contact pressure is increased from 0.05MPa to 0.6MPa,the thermal contact resistance can be reduced by up to 20%;(2)As the surface roughness decreasing,the thermal contact resistance gradually decreases,and the effect of interface contact pressure on the thermal contact resistance was gradually weakening.The thermal contact resistance of the sample with a surface roughness of 0.28 ?m decreased about 40%,50%,and 70%,compared to the surface roughness of 0.54?m,0.96?m,and 2.59 ?m;(3)By decreasing the particle size of the copper powder,the thermal conductivity of low melting temperature alloys which was changed by the copper powder has increased.Considering the low melting temperature alloys modified with 0.5?m copper powder as the thermal interface material has a thermal contact resistance 50%less than the thermal interface material which was mixed by the 5?m copper powder,80%less than what mixed by the 50?m copper powder;(4)The thermal conductivity of low melting temperature alloys modified by 0.5?m copper powder is 50%more than the pure low melting temperature alloys;(5)By establishing the actual solid surface mathematical model,the theoretical model of solid-liquid-solid interface thermal contact resistance is knocked down,and the influence of contact pressure and surface roughness on interface thermal contact resistance is predicted.