添加剂对超硬材料陶瓷结合剂性能的影响

Influence of Additives on Properties of Vitrified Bond for Superhard Materials

以金属Al粉与α-Al2O3微粉作为陶瓷结合剂的添加剂,研究其对陶瓷结合剂抗弯强度、矿物组成及气孔分布等性能的影响。结果表明:金属Al粉添加量为4wt%,在620℃下烧结时,试样抗折强度最高为29.97 MPa,较基础陶瓷结合剂试样提高了10.3%;单独添加α-Al2O3微粉能够提高结合剂的黏度,防止试样在烧成过程中产生不均匀变形,提高陶瓷结合剂的网络致密度;在680℃下烧结,试样抗折强度大幅提高,最高强度为65.46 MPa,较基础陶瓷结合剂提高了140%,并且与陶瓷结合剂发生反应生成霞石(NaAlSiO4),霞石的生成有拓宽烧结范围,抑制裂纹延伸的作用;金属Al粉与α-Al2O3微粉共同加入对陶瓷结合剂抗折强度的提高有更好的效果,在680℃下烧结,当金属Al粉添加量为2wt%,α-Al2O3微粉添加量为30wt%时,试样抗折强度最高为80.33 MPa,较基础陶瓷结合剂试样提高了195.5%;金属Al粉的加入不会影响陶瓷结合剂气孔的形成,气孔分布均匀且较多,具备容纳磨屑与携带冷却液的性能。

The effect of aluminum,α-Al2O3 powders additive on the properties of vitrified bond including bending strength,mineral composition and stomatal distribution was studied.The results showed that the highest bending strength is 29.97 MPa when the addition of aluminum powders are 4wt% sintering at 620 ℃,which is increased 10.3% than that of based vitrified bond.The functions of α-Al2O3 powders are improving samples viscosity which prevents samples deformation,improving samples compact density and improving samples bending strength greatly.The highest bending strength is 65.46 MPa whenα-Al2O3 powders are added only sintering at 680 ℃,which is increased by 140% than that of based vitrified bond,α-Al2O3 would compound with the vitrified bond.And the resultant is nepheline（NaAlSiO4）.Producing nepheline（NaAlSiO4） could widen sintering range and inhibit crack proagation.The highest bending strength is 80.33 MPa,then the aluminum andα-Al2O3 powders are added together,when the addition of aluminum powders is 2wt% and the addition of α-Al2O3 powders is 30wt% sintering at 680 ℃,which is increased 195.5% than that of based vitrified bond.Stomatal distribution is uniform when aluminum powders are added.The vitrified bond could accommodate abrasive dust and carry cooling liquid.