Abstract:Copper-based porous wicks were prepared by powder metallurgy using NaCl powders as pore forming agents. The effects of pore forming agent content and particle size on the porosity, pore structure, equivalent pore size, permeability and capillary pumping performance of porous wicks were investigated. The relationships among the pore structure, equivalent-pore-size and performances were discussed. The results show that, with increasing the pore forming agent content, the porosity of the porous wicks increases obviously, the number of prefabricated pores inside wicks increases significantly, which results in the connecting of prefabricated pores. With decreasing the particle size of pore forming agent, the porosity of the porous wicks reduces slightly, and the size of the prefabricated pores becomes smaller and the distribution tends to be uniform. Interstitial pores and prefabricated pores inside the wick can make up different types of pore channels. The equivalent pore size of wick is closely related to the structure and quantity of pore channels. By changing the content and particle size of the pore forming agent, different pore structure can be produced, and the equivalent pore size of the materials can be controlled. The permeability and capillary pumping performance of porous wicks is not only determined by porosity, but also by pore structure and pore size. Porous wicks with high porosity, small average equivalent pores size and concentrated pore size distribution show better capillary pumping performances.
何达, 汪琳, 刘如铁, 王铸博, 熊翔, 邹俭鹏. 烧结铜基多孔毛细芯的孔隙特征及性能[J]. 粉末冶金材料科学与工程, 2018, 23(4): 389-397.
HE Da, WANG Lin, LIU Rutie, WANG Zhubo, XIONG Xiang, ZOU Jianpeng. Pore characteristic and performance of sintered copper-based porous wicks. Materials Science and Engineering of Powder Metallurgy, 2018, 23(4): 389-397.
[1] MAYDANIK Y F.Loop heat pipes[J]. Applied Thermal Engineering, 2005, 25(5/6): 635-657. [2] CHERNYSHEVA M A, VERSHININ S V, MAYDANIK Y F.Operating temperature and distribution of a working fluid in LHP[J]. International Journal of Heat & Mass Transfer, 2007, 50(13/14): 2704-2713. [3] VERSHININ S V, MAYDANIK Y F.Hysteresis phenomena in loop heat pipes[J]. Applied Thermal Engineering, 2007, 27(5): 962-968. [4] 周蕤. 抗重力环路热管的设计制造及其复合结构毛细芯性能研究[D]. 广州: 华南理工大学, 2014: 11-12. ZHOU Rui.Design and manufacturing of anti-gravity loop heat pipe and study on its composite porous wick[D]. Guangzhou: South China University of Technology, 2014: 11-12. [5] RIEHL R R, SIQUEIRA T C P A. Heat transport capability and compensation chamber influence in loop heat pipes performance[J]. Applied Thermal Engineering, 2006, 26(11/12): 1158-1168. [6] LI J, WANG D, PETERSON G P.Experimental studies on a high performance compact loop heat pipe with a square flat evaporator[J]. Applied Thermal Engineering, 2010, 30(6/7): 741-752. [7] BERTI L F, SANTOS P H D, BAZZO E, et al. Evaluation of permeability of ceramic wick structures for two phase heat transfer devices[J]. Applied Thermal Engineering, 2011, 31(6/7): 1076-1081. [8] AHMED Y M Z, RIAD M I, SAYED A S, et al. Correlation between factors controlling preparation of porous copper via sintering technique using experimental design[J]. Powder Technology, 2013, 175(1): 48-54. [9] KURT A, ATES H.Effect of porosty on thermal conductivity of powder metal materials[J]. Materials & Design, 2007, 28(1): 230-233. [10] MOSADEGHKHAH A, ALAEE M A, MOHAMMADI T.Effect of sintering temperature and dwell time and pressing pressure on Ba0.50.80.23-perovskite-type membranes[J]. Materials & Design, 2007, 28(5): 1699-1706. [11] WU C H.The effects of powder characteristics and sintering processes on the wick properties and thermal performance of flat plate heat pipe[D]. Taibei: Tatung University, 2005: 20-38. [12] NIU W, BAI C, QIU G B, et al.Processing and properties of porous titanium using space holder technique[J]. Materials Science & Engineering A, 2009, 506(1): 148-151. [13] HAO G L, HAN F S, WU J, et al.Damping properties of porous AZ91 magnesium alloy reinforced with copper particles[J]. Metal Science Journal, 2013, 23(4): 492-496. [14] SURACE R, FILIPPIS L A C D, LUDOVICO A D, et al. Influence of processing parameters on aluminium foam produced by space holder technique[J]. Materials & Design, 2009, 30(6): 1878-1885. [15] CUEVAS F G, MONTES J M, CINTAS J, et al.Electrical conductivity and porosity relationship in metal foams[J]. Journal of Porous Materials, 2009, 16(6): 675-681. [16] ZHANG Y P, LI D S, ZHANG X P.Gradient porosity and large pore size NiTi shape memory alloys[J]. Scripta Materialia, 2007, 57(11): 1020-1023. [17] 徐计元, 邹勇, 程林. 环路热管复合毛细芯的孔结构优化与性能研究[J]. 中国电机工程学报, 2012, 32(23): 70-74. XU Jiyuan, ZOU Yong, CHENG Lin.Pore structure optimization and properties of composite wicks for loopheat pipes[J]. Proceedings of the CSEE, 2012, 32(23): 70-74. [18] 徐计元. 环路热管蒸发器毛细结构优化及其性能研究[D]. 济南: 山东大学, 2014: 23-45. XU Jiyuan.Optimization of the capillary structure in loop heat pipe evaporator and research on its performance[D]. Jinan: Shandong University, 2014: 23-45. [19] LI J W, ZOU Y, CHENG L, et al.Effect of fabricating parameters on properties of sintered porous wicks for loop heat pipe[J]. Powder Technology, 2010, 204(2/3): 241-248. [20] XIN G M, CUI K H, ZOU Y, et al.Development of sintered Ni-Cu wicks for loop heat pipes[J]. Science in China Series E: Technological Sciences, 2009, 52(6): 1607-1612.