Effect of Al:P ratio on bonding performance of high-temperature resistant aluminum phosphate adhesive. (July 2020)

• Record Type: Journal Article
• Authors: Wang, Mingchao; Zhang, Jing; Tong wei, ; Zhou, Qingjun; Li, Zepeng
• Is Part Of: International journal of adhesion & adhesives. Volume 100(2020)
• Publication Date: 2020-07
• Subjects: Aluminum phosphate adhesive -- High-temperature resistant -- Al:P ratio -- Bonding performance -- Thermal shock resistance -- Heating process; Adhesion -- Periodicals; Adhesives -- Periodicals; Adhésion (Physique) -- Périodiques; Adhésifs -- Périodiques; Adhesie; Kleefstoffen; Adhesion; Adhesives; Periodicals; 668.3
• DOI: 10.1016/j.ijadhadh.2020.102627
• Languages: English
• ISSNs: 0143-7496

Abstract

Abstract: A series of high-temperature resistant aluminum (Al) phosphate (P) adhesives with different Al:P ratios were prepared using Si as the sole additive. The influence of Al:P ratio on the temperature-dependent composition and structural evolution of the adhesives and their bonding performance were systematically analyzed. The conversion of aluminum metaphosphate to aluminum orthophosphate during the heating process from 700 °C to 900 °C decreased with increasing Al:P ratio, which reduced the generation of micro cracks inside the adhesive. Higher Al:P ratios (≥1:1) were favorable for the generation of alumina, which then reacted with silicon oxide to form mullite phase at high temperatures. No mullite phase was generated for Al:P ratios lower than 1. Accordingly, increasing Al:P ratio effectively improved the bonding performance and thermal shock resistance of the adhesive. The bonding strength of adhesive with an Al:P ratio of 1:0.85 after calcination at 1300 °C was 35.7% and 112%, respectively, higher than those of adhesives with Al:P ratios of 4:5 and 1:2. Besides, the retention rates of their bonding strength were 48.8%, 28.6% and 7.9%, respectively, after 15 thermal shocks based on air-cooling from 1300 °C to RT.