Solid Phase Graft Polymerization of Starch with Methyl Methacrylate by γ-Irradiation and Chemical Initiation
Post Date: 04 Sep 2010 Viewed: 471
In this paper, the effect of composition on the properties of the glass used for vitrified bond was studied. As well as the vitrified bond for diamond tool was analysed through testing thermal espanding, refractoriness, strength and wettability of bond by XRD and SEM.1. Through researching three systems of Na20-B203-Si02, Li20-B203-Si02, K2O-B2O3-SiO2, it is found that refractoriness of Na20-B203-Si02 was 630-650 , the bend strength was 55. 4MPa, and it" s thermal expanding and wettability is proper, So the system of Na20 BA-Si02 was one of the best glasses of low temperature bond.2.The effect of chemical composition of PbO, CuO, A1203 on glass used for the bond was researched. It is indicated that when adding some PbO, the wet angle of the bond reduces from 58to 3? , flowing property increases from 130% to 150%-160%, and bending strength will be improved under sintering temperature, but it would increase thermal expanding ratio of the bond. When the adding amount was within 3%-4%, all the properties of bond were good. 3.Through studying the effect of alloy HZ812, Cu, Al, metal power was follows on the bond performance, when adding 8%-10% into the bond. The performance of the bond: bending strength increases from 55.4 MPa to 67 MPa, impact strength increases from 2KJ/m2 to 4KJ/m2 .4. The component of the best low-vitrified bond was the system of NaABA-Si02 was as basic glass, adding 3%-4% PbO and 8%- 10% alloyHZ812. The properties of the bond were:refractoriness of the bond : 650~750,thermal expanding ratio : <5. 5X lO-6C-1, end strength of the bond : 55MPa-66. 5MPa,and other properties are good.The vitrified bond Diamond tool made of above materials was found having good wear-resistant property.