The Effect Of Rare Earth Oxides On The Structure And Mechanical Properties Of High Aluminum Silicate Glass

In this paper,lithium-aluminium-silicate system high-aluminium silicate glass is taken as research object,series of glass samples are prepared by doping Y₂O₃and La₂O₃,and the effects of rare earth oxides Y₂O₃and La₂O₃on the structure and mechanical properties of high-aluminium silicate glass are studied by means of various experimental analysis methods of structure and mechanical properties.It was shown that the Si-O_b-Si bending vibration peak at 470 cm^-1and the composite vibration summit at 1050 cm^-1in the Raman and IR spectra were enhanced and then weakened,indicating that Y₂O₃doping could complement the network structure of the high aluminosilicate.By XPS and solid-state NMR peak splitting,it was found that Y₂O₃would act as a network modifier into the high aluminosilicate structure with a strong agglomerative effect,providing non-bridging oxygen,promoting the transformation of[Al O₆]and[Al O₅]to[Al O₄]and complementing the network structure of high aluminosilicate glasses,but with increasing doping,Y₂O₃caused structural distortion and preferentially destroyed the silicon-oxygen network structure.Therefore,with the doping of Y₂O₃,the degree of network polymerisation of the high aluminosilicate glass shows a trend of first increasing and then slowly decreasing.There is also a tendency for flexural strength,Vickers hardness,and elastic modulus to first increase and then slowly decrease,as the flexural strength was increased from 96.3 Mpa to 110.2 Mpa and then decreased in a stepwise fashion to 102.8 Mpa,the Vickers hardness increases from 632.4 Mpa to 694.3Mpa,and then gradually decreases to a hardness of 657.6 Mpa,and the elastic modulus increasing from 83.3 Gpa to 88.9 Gpa and then decreasing in a stepwise fashion.The density and molar volume of the glass showed a trend of rapid increase and then a slow increase from 2.4116 g/cm³to 2.4416 g/cm³.In a comprehensive view,when the doping amount of Y₂O₃was 0.2 mol%,the network polymerisation of the high aluminosilicate glass was the highest and the mechanical properties were the best.With the doping of La₂O₃,the bending vibration peaks of Si-O_b-Si,the antisymmetric stretching vibration peaks of Si-O_nband the antisymmetric stretching vibration peaks of Si-O_b-Si in the IR and Raman spectra showed a trend of first enhancement and then weakening,and the[Al O₄]content increased and the[Al O₆]content decreased through the split-peak fitting of the Al spectrum in XPS,which indicated that in the high aluminosilicate The doping of La₂O₃in the glass,La³⁺will enter the network structure interstices of the glass and provide free oxygen,thus promoting the transformation of Al₂O₃octahedra into Al₂O₃tetrahedra,but the doping of excessive La₂O₃,due to its large ionic size,will trigger structural distortion and damage the structure of the high aluminosilicate glass.For the high aluminosilicate glass,the degree of polymerization of the lattice structure increases and then decreases with La₂O₃doping,and the bending strength,Vickers hardness,and elastic modulus exhibit the same trend,where the flexural strength is increased from 96.3 Mpa to 106.4 Mpa and then decreased back to 101.5 Mpa,the hardness of the The Vickers increases from 632.4 Mpa to 686.6 Mpa and then decreases back to 658.7 Mpa.The density and molar volume of high aluminosilicate glass show a continuous increase with the doping of La₂O₃,from 2.4116 g/cm³to 2.4528 g/cm³.When the doping amount of La₂O₃is 0.4 mol%,the best overall mechanical properties.