CAJ | 학술논문

通过在金刚石表面镀钛来改善金刚石和铝基体之间的弱界面结合,并用气压浸渗法制备体积分数为60%的镀钛金刚石/铝复合材料.研究镀钛后金刚石颗粒的物相组成、不同镀层厚度和不同颗粒尺寸下复合材料的热导率;用H-J和DEM模型预测复合材料的热导率,并将预测结果与实验值进行对比.结果表明,镀钛后金刚石颗粒的物相由金刚石、碳化钛和钛三相组成;随着镀层厚度的增加,界面传热系数减小,复合材料的热导率减小;颗粒的尺寸越小,这种变化趋势越明显;相对于 H-J 模型,DEM 模型更能准确地预测镀钛金刚石增强的复合材料的热导率;通过计算得出镀钛金刚石/铝复合材料的临界镀层厚度为1.5μm,当超过此临界镀层厚度时,镀层反而不利于复合材料热导率的提高.
통과재금강석표면도태래개선금강석화려기체지간적약계면결합,병용기압침삼법제비체적분수위60%적도태금강석/려복합재료.연구도태후금강석과립적물상조성、불동도층후도화불동과립척촌하복합재료적열도솔;용H-J화DEM모형예측복합재료적열도솔,병장예측결과여실험치진행대비.결과표명,도태후금강석과립적물상유금강석、탄화태화태삼상조성;수착도층후도적증가,계면전열계수감소,복합재료적열도솔감소;과립적척촌월소,저충변화추세월명현;상대우 H-J 모형,DEM 모형경능준학지예측도태금강석증강적복합재료적열도솔;통과계산득출도태금강석/려복합재료적림계도층후도위1.5μm,당초과차림계도층후도시,도층반이불리우복합재료열도솔적제고.
@@@@Titanium coating on diamond surface was adopted to improve the weak interface bonding between diamond and aluminum matrix. The Ti-coated diamond/Al composites were fabricated by gas pressure infiltration with a 60%volume fraction of diamond. The phase composition of diamond after coating titanium and the thermal conductivity (TC) of Ti-coated diamond/Al composites under different coating thicknesses and different particle sizes were also studied. The predicted results of the H-J and DEM models were compared with the experimental values. The results show that, the diamond particles are composed of three phases:diamond, TiC and Ti?along with the increase of the coating thickness, interface heat transfer coefficient and TC of composites decrease, the smaller the particle, the more obvious the tendency. Compared with the H-J model, the DEM model gives more accurate predictions for Ti-coated diamond/Al composites. The critical coating thickness was calculated to be 1.5 μm for diamond/Al composites. When the coating thickness exceeds this critical value, the coating is detrimental to improving the TC.