Joining Ceramics Research Articles

Joining C/C–SiC composite and Ti60 alloy using a semi-solid TiNiCuNb filler

This paper developed an innovative pressure-free contact reaction brazing technique that facilitated joining ceramics at low temperatures. Using this method, a semi-solid TiNiCuNb filler was employed to join C/C–SiC composite and Ti60 alloy. By facilitating elements’ diffusion through the partial liquid of semi-solid TiNiCuNb alloy, Ti could be introduced into this alloy without pressure, and the complete melting was achieved above 950 °C. Based on this, Ti60 alloy was joined to C/C–SiC composite below its β-transus temperature. Significant reaction differences between C/C and SiC with filler were found, mainly due to the different solubility and diffusion characteristics of C and Si in liquid filler. SiC exhibited higher sensitivity to temperature changes and was more prone to overreaction to induce defects. At 1010 °C, the maximum shear strength of 22.5 MPa was obtained due to the moderate reaction of both C/C and SiC with filler. This work contributed to manufacturing lightweight brake systems.

Vacuum brazing SiC to Mo using Nb0.74CoCrFeNi2 eutectic high-entropy alloy filler

Joining ceramics and metals is important to expand their application scope in the nuclear industry. The brazing of SiC and Mo was conducted using a Nb0.74CoCrFeNi2 eutectic high-entropy alloy filler. The microstructure and mechanical properties of the joints were examined at different brazing temperatures. As the temperature increased, the eutectic structure gradually disappeared, and a layered structure was formed at the brazed joint. An increase in the MoNi phase content can improve joint strength owing to differences in the thermal expansion coefficient and lattice mismatch between phases. The joints exhibited a maximum shear strength of 62 MPa at 1300 °C. Finite element analysis results demonstrated that the presence of a Cr0.46Mo0.4Si0.14 phase causes the concentration of residual stress. Brittle fracture occurred mainly in the Cr0.46Mo0.4Si0.14 phase, causing the rupture of the joint. This study provides valuable insights into the use of eutectic high-entropy alloys as fillers to establish a strong and reliable connection between ceramics and metals.

Interfacial strengthening mechanism of C/C/Nb0.74CoCrFeNi2/Nb brazed joints: Stress-relieving effects of the FCC phase

Joining ceramics and metals has long been a key issue for manufacturing structures that are resistant to high temperature. This study joined a carbon-fiber-reinforced carbon-matrix (C/C) composite and Nb using a Nb0.74CoCrFeNi2 eutectic high-entropy alloy filler, and the evolution mechanism of the microstructure and mechanical properties of the joints were systematically studied. The eutectic structure composed of face-centered cubic (FCC) and Laves phases gradually disappeared with the increasing temperature, while the Nb(s,s) layer thickness increased gradually. The lattice mismatch was ∼97% and ∼2.8% at the Cr23C6/C/C and FCC/C/C interfaces, respectively. Considering differences in the coefficient of thermal expansion and lattice mismatch, an increase in FCC phase content at the C/C interface is conducive to reinforcing the joint strength. At 1260 °C, the combined effects of the highly deformable FCC phase and high-strength Cr23C6 increased the strength of the mixing zone, causing fracture to occur in the Nb(s,s) layer. These results are expected to contribute to further improving the joining of dissimilar materials.

A New Strategy for Dissimilar Material Joining between SiC and Al Alloys through Use of High-Si Al Alloys

Joining metals and ceramics plays a crucial role in many engineering applications. The current research aims to develop a simple and convenient approach for dissimilar material joining between SiC and Al alloys. In this work, Al alloys with Si contents varying from 7 wt.% to 50 wt.% were bonded with SiC at a high temperature of 1100 °C by a pressure-less bonding process in a vacuum furnace, and shear tests were carried out to study the bonding strength. When using low-Si Al alloys to bond with SiC, the bonding strength was very low. The bonding strength of Al/SiC joints increased significantly through the use of high-Si Al alloys with 30 wt.% and 50 wt.% Si. The shear strength achieved (28.8 MPa) is far higher than those reported previously. The remarkable improvement in bonding strength is attributed to the suppression of brittle interfacial products and reduced thermal stresses. This research provides a new strategy for joining between SiC and a wide range of Al alloys through the use of high-Si Al alloys as the interlayers.

Joining of ceramic to metal by friction welding process: A review

In this paper, the recent progress in friction welding of alumina along with its various composites to metals is thoroughly investigated and compared. Among the existing methods of joining ceramics to metals, the friction welding process seems to be a reliable approach that provides promising joint properties. A relationship is established between processing parameters, their resultant microstructures, and their associated mechanical properties. The material properties and the environmental factors are taken into account while manifesting this comparison. The influence of various factors such as rotations per minute (r/min), friction pressure, and friction time on mechanical properties is critically analyzed. However, several challenges that must be addressed appropriately to achieve these joints and to fabricate the same have been discussed.

State of Art:Joining of Microwave Processed Materials

Microwave processing is relatively advanced and unfamiliar technique of joining metals and ceramics. Microwave energy has been effectively used in the processing of different materials. It has been introduced in the field of manufacturing and design due to its various advantages over other welding/joining techniques such as - short heating time, hybrid heating, saving energy etc. Microwave heating leads to generation of inverted temperature profile and provides selective heating and as well as volumetric heating. Joining of bulk pieces of similar/dissimilar metals which have high thermal conductivity is really challenging. Microwave processing has numerous advantages over traditional methods of heating. It has been commonly used in various industrial, scientific and medical applications for processing, drying and heating. In the past years, various works has been done on polymers, ceramics except metals by using microwave radiations. Many initiatives have been taken to explore this advanced and emerging technique in various fields of engineering.

NUMERICAL SIMULATION ON JOINING OF CERAMICS WITH METAL BY FRICTION WELDING TECHNIQUE

The joining of ceramic and metals can be done by different techniques such as ultrasonic joining, brazing, transient liquid phase diffusion bonding, and friction welding. Friction Welding is a solid state joining process that generates heat through mechanical friction between a moving workpiece and a stationary component. In this article, numerical simulation on thermal analysis of friction welded ceramic/metal joint has been carried out by using Finite Element Analysis (FEA) software. The finite element analysis helps in better understanding of the friction welding process of joining ceramics with metals and it is important to calculate temperature and stress fields during the welding process. Based on the obtained temperature distribution the graphs were plotted between the lengths of the joint corresponding to the temperatures. To increase the wettability, aluminium sheet was used as an interlayer. Hence, numerical simulation of friction welding process is done by varying the interlayer sheet thickness. Transient thermal analysis had been carried out for each cases and temperature distribution was studied. From the simulation studies, it is found that the increase in interlayer thickness reduces the heat affected zone and eventually improves the joint efficiency of alumina/aluminum alloy joints.

An analysis of deformation mechanism in the Si3N4–AgCuTi+SiCp–Si3N4 joints by digital image correlation

Abstract The composite filler shows more advantages than traditional brazing alloys, and has been widely introduced into joining ceramics or ceramics to metals. However, the underlying formation and strengthening mechanisms remained uncertain in the joint. In current research, SiCp (p = particle) was incorporated in Ag–Cu–Ti brazing alloy for joining Si 3 N 4 ceramic. Nanoindentation method was introduced for probing the mechanical properties of reaction phases between the brazing alloy and SiCp. A novel formation mechanism model was thus proposed. In addition, optical microscope (OM) in conjunction with digital image correlation (DIC) techniques has been first applied to elucidate the deformation mechanism in the joint with and without SiC incorporation. The following reasons were believed to strengthen the brazed joint: load-transfer ability of SiCp, plastic relaxation in the brazing layer and CTE reduction of the composite filler.

Joining of ceramic materials using niobium and niobium-based alloys

The results of investigations of wetting of Al2O3, ZrO2, AlN, VK94-2, and porcelain using various niobium-containing alloys are presented. A method for brazing ceramic materials with niobium by the contact-reactive methods through nickel and also the conditions of joining ceramics with niobium by pressure welding are described.

Progress in Joining Ceramics to Metals

The research and development of joining methods of ceramics to metals, especially brazing, diffusion bonding and partial transition liquid phase bonding, were introduced. Some opinions were put forward. For new composites emerging, it is necessary to develop new joining methods, particularly in the field of high temperature technique for joining ceramics to superalloys.

Finite Element Simulation of Thermal Residual Stresses in Joining Ceramics with Thin Metal Interlayers

Finite element analysis was used to estimate thermal residual stresses developed in silicon nitride bodies bonded by metallic interlayers. Stresses were calculated for various characteristic metals, namely, Ni, Al, and Si, assuming elastic and elastic‐plastic behavior. The relative importance of the metal properties, such as thermal expansion coefficient, stiffness and ductility, has been evaluated. Two different joint geometries, butt and lap, have been used in stress calculations, and special care was taken in the mesh generation, to obtain comparable results. The yield stress of the interlayer material rather than thermal expansion mismatch is the critical factor in thermal residual tensile stress buildup inside ceramic adherents.

New approaches to joining ceramics for high-temperature applications

Micro-designed multilayer interlayers have been used to join both oxide and non-oxide ceramics. The approach allows the formation of ceramic-ceramic joints with high melting point metals at temperatures that are typically several hundred degrees lower than those required for more conventional joining methods. The new joining approach employs a thin transient liquid phase (TLP) layer to allow joining by a brazing-like process. Several distinct interlayers have been used to join alumina ceramics successfully; work using Ni-based interlayers has demonstrated the potentially beneficial impact of “reactive” metal additions to the TLP. The method has also been applied to the joining of silicon-based ceramics, and has led to the fabrication of joints with reproducibly high strengths.

New Strategies for Joining Ceramics for High-Temperature Applications

New Strategies for Joining Ceramics for High-Temperature Applications

Low temperature routes to joining ceramics for high-temperature applications

The ability or inability to join ceramics will expand or contract the potential use of ceramics in a wide range of applications. There is a need for fundamental research on the properties of joints between ceramics formed by any method, and a parallel need for methods of ceramic joining that are compatible with mass production of joined assemblies and that will yield reliable and strong joints. The need for reliable, mass production oriented methods of joining addressing high-temperature high-stress applications is particularly urgent. The authors efforts have focused on exploring and development new approaches to joining that combine the processing advantages of liquid-state bonding methods (brazing) with the ability to use refractory metal interlayers normally associated with solid-state bonding methods (diffusion bonding). The approaches under investigation also seek to combine a low processing temperature with the potential for subsequent use at temperatures that approach or exceed the joining temperature.

Simulation of Sintering Experiments in Single-Mode Cavities

ABSTRACTThe use of single-mode cavities has been recognized as a viable technique for sintering and joining ceramics and for creating microwave plasma for materials processing. It is often reported, however, that tuning these cavities at lower and higher temperatures critically depends on the types of materials being processed, the variation of ε* as a function of temperature, the size and shape of samples, and the overall heating system configuration with and without insulation.In this paper we use the finite-difference time-domain technique to address the performance of the single-mode cavity heating system under a wide variety of heating conditions and system configurations. Specifically, practical issues such as limiting values of sample sizes, the dependence of optimal sample sizes on the complex permittivity of materials under test, the role of sample shape on enhancing uniformity of heating patterns, and various tradeoffs involved in utilizing various cavity modes and/or SiC rods as stimulus for heating large samples are evaluated.

Third international conference on joining ceramics, glass and metal : Bad Nauheim, FRG, 26–28 April, 1989

Third international conference on joining ceramics, glass and metal : Bad Nauheim, FRG, 26–28 April, 1989

金属とセラミックスの接合における諸問題 セラミックス／金属接合における圧力の効果

金属とセラミックスの接合における諸問題 セラミックス／金属接合における圧力の効果

878. Method of joining ceramics to metals without the burning-in of metal powders: A Ya Makarkin and I P Metelkin, Tr Konf Elektron Tekhn, 1, 1966, 165 ( in Russian)

878. Method of joining ceramics to metals without the burning-in of metal powders: A Ya Makarkin and I P Metelkin, Tr Konf Elektron Tekhn, 1, 1966, 165 ( in Russian)

Paper 8: Recent Developments in Engineering Ceramics

Ceramics in the context of this paper will be considered to be inorganic non-metallic materials which are shaped when in a finely divided form, followed by a high-temperature sintering treatment. A better understanding of the properties of ceramics (e.g. alumina) can be gained by the study of the properties of the material in single crystal form (e.g. sapphire). The properties of different materials can be related to their crystal structure. This scientific pursuit has led to a number of new materials (silicon nitride, Si3N4, and boron nitride, BN). Compared with metals ceramics compete favourably on account of their high strength at high temperatures, good wear and corrosion resistance. Their main drawbacks are brittleness and failure by thermal stresses. The application of new methods of fabrication has been aimed at producing ceramics of high density and to accurate dimensions. The properties of the following materials will be discussed in some detail: alumina, Al2O3; silicon nitride, Si3N4; silicon carbide, SiC; and boron nitride, BN. It will be demonstrated that different methods of fabrication can result in widely differing properties of the same material. Small grain size and high density are essential for good mechanical strength. Methods of joining ceramics to metal will be discussed. Some important applications will be reported and consideration will be given to problems facing the designers.