MoSi2 is presently regarded as the most important material for electrical heating and as one with huge potential for high temperature structural uses. MoSi2 and MoSi2 matrix composites were prepared by self-propagatin...MoSi2 is presently regarded as the most important material for electrical heating and as one with huge potential for high temperature structural uses. MoSi2 and MoSi2 matrix composites were prepared by self-propagating high temperature synthesis （SHS）. Pure MoSi2 was obtained and a compound of MoSi2 and WSi2was synthesized in the form of predominant solid solution （Mo,W）Si2. By adding aluminum of 5.5 at.% to Mo-Si, the crystal structure of MoSi2 changed into a mixture of tetragonal Cllb MoSi2and hexagonal C40 Mo（Si,Al）2. The （Mo,W）Si2-Mo（Si,Al）2-W（Si,Al）2 composite materials were synthesized by adding aluminum of 5.5 at.% to Mo-W-Si. However, if the amount of the added aluminum was not larger than 2.5 at.%, it did not have any significant effect. SHS is an effective technology for synthesis of MoSi2 and MoSi2 matrix composites.展开更多
Wear behaviors of MoSi2 doped with La2O3 against SiC under different loads at 1000 oC in air were investigated by using an XP-5 type high temperature friction and wear tester. The worn surfaces and phases of the sampl...Wear behaviors of MoSi2 doped with La2O3 against SiC under different loads at 1000 oC in air were investigated by using an XP-5 type high temperature friction and wear tester. The worn surfaces and phases of the samples were analyzed by scanning electron microscopy （SEM） and X-ray diffraction, respectively. Results showed that the addition of La2O3 could obviously improve wear resistance of MoSi2. Because of the formation of MoO3 phase on the worn surface, La2O3/MoSi2 composite mainly exhibited oxidation and abrasive wear, which was different from the wear form of MoSi2 such as adhesion, oxidation and abrasion.展开更多
基金This project was financially supported by the National Natural Science Foundation of China (No. 50025412)
文摘MoSi2 is presently regarded as the most important material for electrical heating and as one with huge potential for high temperature structural uses. MoSi2 and MoSi2 matrix composites were prepared by self-propagating high temperature synthesis （SHS）. Pure MoSi2 was obtained and a compound of MoSi2 and WSi2was synthesized in the form of predominant solid solution （Mo,W）Si2. By adding aluminum of 5.5 at.% to Mo-Si, the crystal structure of MoSi2 changed into a mixture of tetragonal Cllb MoSi2and hexagonal C40 Mo（Si,Al）2. The （Mo,W）Si2-Mo（Si,Al）2-W（Si,Al）2 composite materials were synthesized by adding aluminum of 5.5 at.% to Mo-W-Si. However, if the amount of the added aluminum was not larger than 2.5 at.%, it did not have any significant effect. SHS is an effective technology for synthesis of MoSi2 and MoSi2 matrix composites.
基金supported by the National Natural Science Foundation of China (51071133)
文摘Wear behaviors of MoSi2 doped with La2O3 against SiC under different loads at 1000 oC in air were investigated by using an XP-5 type high temperature friction and wear tester. The worn surfaces and phases of the samples were analyzed by scanning electron microscopy （SEM） and X-ray diffraction, respectively. Results showed that the addition of La2O3 could obviously improve wear resistance of MoSi2. Because of the formation of MoO3 phase on the worn surface, La2O3/MoSi2 composite mainly exhibited oxidation and abrasive wear, which was different from the wear form of MoSi2 such as adhesion, oxidation and abrasion.
