Preparation Of Heat-resistant 600? Adhesive

With the development of science and technology,the traditional high-temperature resistant adhesives have been unable to meet the needs of modern industrial and technological development.There are more stringent requirements for high-temperature resistant adhesives especially in the rapid development of the aerospace field.The organic/inorganic hybrid adhesives have high room-temperature adhesive strength and good heat resistance at high temperature,which possess both the advantage of organic adhesives and inorganic adhesives.Therefore,the preparation of organic/inorganic hybrid high temperature resistant adhesives has a practical application significance in the field of aerospace.In this paper,a rare earth modified alcohol-soluble phosphate is used as the key component which was added with a certain amount of phenolic resin,silicone resin,phosphazene epoxy resin,and a kind of 80?/4 h curing hybrid adhesive is prepared with the Al₂O₃,B₄C,Al₂O₃ chopped fiber and Si₃N₄ chopped fiber mixture as the inorganic fillers.After curing,the shear strength of the prepared adhesive is 15.8 MPa at room temperature,the shear strength is 13.6 MPa at 600??keeps for 10min?and the elongation is 5.6%.The mechanical properties,heat resistance,crystal structure and microstructure of the adhesive are analyzed by means of SEM,FT-IR,TG and XRD respectively.The adhesive shows excellent adhesion performance for various materials,such as alloy steel/alloy steel,SiC/SiC,composites/alloy steel,titanium alloys/titanium alloys,etc.And it has good peel strength,for bonding the treated quartz cloth to high temperature alloy steel,the peel strength at room temperature and at 200?is 2.48kN/m and 1.87 kN/m respectively.After being placed in the open environment for 3hours or in an airtight environment for 8 hours,the shear strength after curing significantly reduces.The TG analysis for the adhesive indicates that the weight loss of the adhesive was 2%at 1000?.The resistance to medium,the mass loss characteristic in the space environment,and the heat aging properties of the adhesive are examined.The results show that the adhesive has a low mass loss,however its shear strength severely reduces after water boiling,which is 1.2 MPa after water boiling for 8 hours,drops by 93%.The shear strength is 13.8 MPa which has been aging at 600?for 125 h,and it indicates that the adhesive has excellent aging resistance at 600?,which can be used for a long term at600?.The XRD and SEM test methods are used to analyze the change of microstructure and crystal structure after aging,and the results indicate that there is no change in the microstructure and crystal structure of the adhesive after aging at 600?.