Theoretical And Experimental Study On Highly-Efficience And Liquid-Cooled Heatsink Based On 3D Printing Technology

Semiconductor laser has many advantages such as small size, light weight, high electro-optic conversion efficiency and ease to be integrated. So it has a wide range of application in military, science and technology, medical treatment and other fields. The cooling technology of bar is the one of the core technologies in laser packaging process. High power semiconductor laser usually uses micro-channel heat sink to deal with redundant heat. The traditional preparative technique of microchannel heat sink by welding Oxygen-free copper sheets seriously restricted the improvement of beam quality and the service life due to possessing many shortcomings. For example, heat sink does not match with laser chip in thermal expansion coefficients. The welding process of Oxygen-free copper could be introduced in extra welding heat resistance. And the material of heat sink is easy to be corroded by deionized water during use. Therefore, the research on the new preparative technique of heat sink to improve the beam quality and service life of semiconductor laser has important significance.Firstly this paper based on characteristics of selective laser sintering(SLM) technique which is the one of 3D printing technology, designed a double-hole microchannel heat sink. Then the paper simulated and theoretically analyzed the two-hole microchannel heat sink using commercial CFD software Fluent. By analyzing the mass and heat transfer of the two-hole microchannel heat sink using k-? standard turbulence model as the physical model, the paper obtained the pressure drop, thermal resistance and microchannel's flowing velocity at different Flowing velocity. And after the structure has been optimized according to the simulation results, the paper obtained the model of two-hole heat sink which can theoretically satisfy the cooling requirements of high-power semiconductor diode lasers. Finally, this paper designed a three-hole microchannel heat sink according to the structure of double-hole microchannel heat sink and then simulated simulating pressure drop and heat resistance.This paper prepared designed microchannel heat sink on the M270 EOS molding machine and tested pressure drop and thermal resistance. The experimental results show that thermal resistance of 4 structures is in agreement with the results of CFD numerical analysis,which verified the reliability of CFD simulation results. The pressure drop value of M3 structure heat sink optimized is about 0.5bar and the thermal resistance value is 0.363K/W under Flowing rate=18L/h commonly used in industry. The pressure drop of three-hole heat sink is about 0.6bar and resistance is 0.411K/W. it can meet the cooling demand of high power semiconductor lasers.This paper tested the "Smile" effect value of 80 W bar packaged with microchannel heat sink when working correctly. The test results show that the "smile" effect value of bar's spectrum can be effectively controlled below 1?m,which test that SLM heat sink can meet the requirements 80 W laser bar on the beam quality.This paper investigated the method using selective laser melting technology to manufacture micro-channel heat sink. Compared with the traditional method by welding oxygen-free copper sheets, the new manufacturing method has important significance to solve the shortcomings in the process of traditional preparing micro-channel heat sink.