Contributions to the interfacial adhesion in co-sintered bilayers

Abstract

The adhesive strength of co-sintered bilayers is influenced by several factors, including the nature of bonding along the joined interface, residual stresses evolved during processing, and the sintered properties of the individual layers. Here these separate contributions are isolated through careful control of the co-sintering process for W/Al 2 O 3 bilayers, and in particular through control of the W-layer properties by using the process of activated sintering. Four-point bending delamination tests are used to evaluate adhesion and strength of the bilayers, and the interfacial fracture mechanics of the system is numerically studied using finite element simulations. Improvements in sintered density are found to increase the adhesive strength of the system only up to a point, beyond which shrinkage mismatch compromises the intrinsic toughness of the interface.

Interface Reactivity and Induced Phenomena during Sintering in a Model Steel/Cemented Carbide Bimaterial

“…Powder metallurgy is an efficient way for processing various multilayered materials, including: metal-metal (e.g., steel/steel, [1] 316L/17-4PH, [2] Ti/Al 3 Ti [3] ) ceramic-ceramic (e.g., PZT/PZT, [4] Al 2 O3/Ti 3 SiC 2 , [5] Al 2 O 3 /ZrO 2 [6] ), and metal-ceramic (e.g., W/Al 2 O 3 , [7] Ti/TiB 2 /B, [8] NiCr/ ZrO 2 , [9] , steel/Al 2 O 3 [1] ) The model bimaterial studied here was designed a few years ago to combine toughness and hardness properties with co-sintering requirements. [10,11] It is based on the elements W, C and Fe: a Fe-W-C ''Fe base'' (mass composition Fe-6.5%W-0.95%C) and a WC-Fe '''WC base'' cemented carbide (mass composition W-6.6%Fe-5.9%C).…”

Design and processing parameters of La2NiO4+δ-based cathode for anode-supported planar solid oxide fuel cells (SOFCs)

“…In particular, the adhesion issues of the RuddlesdenePopper oxide cathode have been addressed repeatedly [47,50,65], signifying that it is difficult to achieve sufficient bonding strength and suppress unwanted chemical interactions at the same time [47]. Because the adhesion strength develops through mechanical interlocking resulting from the joining and consolidation of particles at the interface, the degree of sintering is one of the main factors controlling the adhesive strength of multi-layer ceramics [66]. Therefore, the linear sintering shrinkage of single-phase LNO was measured and compared with those of the LNOeGDC composites using a dilatometer in Fig.…”

Mechanical properties of interface layers between cosintered alumina and spinel compacts

“…Their application areas range from electronic packaging applications such as multilayer ceramic capacitors to thin film-substrate systems widely used in the microelectronics industry. [1][2][3] Cosintering process is to sinter two materials to one piece while they are in contact with each other; therefore, it can produce bimaterial with novel properties. Many researchers have studied cosintering process for different kinds of materials to understand and analyse the formation of mismatch stress due to difference in shrinkage strain of materials during cosintering and cooling processes.…”

“…Their application areas range from electronic packaging applications such as multilayer ceramic capacitors to thin film–substrate systems widely used in the microelectronics industry. 1–3…”