Self healing ability and strength recovery of different laminated Al2O3 cutting tool composites

Abstract

The lifetime of ceramic tool is decreased because of the extension of cracks, and it will be prolonged if the cracks can be self healed. The healing ability of laminated Al2O3 cutting tool composites (Al2O3-(WC-Co)-MgO / Al2O3-TiC-MgO) were assessed. For determining which laminated structure and the healing condition was the best for the composite, the flexural strength and recovery rates were measured and different healing condition were used. XRD, EDS and SEM technology were carried out to identify their compositions and microstructures after the healing. The number of cracks filled with TiO2, crack size and the oxide content effect were utilized to explain why the flexural strength and recovery rates of laminated Al2O3 cutting tool composite after the healing were different. A single particle model was utilized to identify the relation between the threshold time, grain size and the self healing temperature of the composites.

Research Progress of Laminated Composite Ceramic Cutting Tools

“…[ 46 ] By establishing a single‐particle self‐healing model, the nature of self‐healing was theoretically explored. [ 47 ] The evolution diagram of self‐healing mechanism of laminated Al 2 O 3 tool composites is shown in Figure . [ 47 ]…”

“…[ 47 ] The evolution diagram of self‐healing mechanism of laminated Al 2 O 3 tool composites is shown in Figure . [ 47 ]…”

“…[46] By establishing a single-particle selfhealing model, the nature of self-healing was theoretically explored. [47] The evolution diagram of self-healing mechanism of laminated Al 2 O 3 tool composites is shown in Figure 7. [47] The application of graphene in laminated ceramic structures was expected to improve the mechanical properties of ceramic materials more effectively.…”

“…[47] The evolution diagram of self-healing mechanism of laminated Al 2 O 3 tool composites is shown in Figure 7. [47] The application of graphene in laminated ceramic structures was expected to improve the mechanical properties of ceramic materials more effectively. Graphene is a kind of sp 2 hybrid connected carbon atom tightly packed into a single 2D honeycomb lattice structure of new materials, which has a 2D sheet structure, high specific surface area, and excellent mechanical properties, [48] and is considered as a revolutionary material in the future.…”

Oxidation‐induced crack‐healing behavior of SiC‐Al2O3‐TiB2 composites at 600°C–800°C

“…Most studies on ceramic crack healing [16][17][18]22,23,27,28 have focused on the high-temperature stage (above 1000 • C) or slow healing at low temperatures, although for cracks to be repaired, the energy consumed is also significant, so it is necessary to achieve rapid repair of ceramic cracks at lower temperatures. Boron, titanium, borides, and titanium compounds can also be used as healing agent, [34][35][36][37][38][39][40] which undergo oxidation at lower temperatures and produce volume expansion, while generating oxidation products with viscosity that can flow into and fill the cracks and have good healing effect on microcracks. [41][42][43] We further selected TiB 2 as a healing agent for our study based on previous studies, 42 the healing mechanism was further investigated based on the study of Osada et al 44,45 In this paper, SiC/Al 2 O 3 /TiB 2 ceramic materials with glass powder as the sintering aid were prepared by plasma discharge sintering technique.…”