Low-temperature Sintering
Low-temperature sintering (LTS) is a process by which a powder is sintered to produce a metal component or ceramic object, using temperatures lower than the traditionally used temperature for sintering. This technology is becoming increasingly attractive for a number of reasons including the ability to achieve mechanical, electrochemical, and optical properties not obtainable with conventional sintering, and for its potential for improving cost-effectiveness and reduced manufacturing times.
The primary benefit of low-temperature sintering is that it achieves mechanical properties in parts that may not have been attainable using traditional sintering temperatures. By maintaining the part components together at a lower temperature, the parts are less likely to fail due to thermal shock or creep. Low-temperature sintering also creates dense, uniform material structures with excellent mechanical properties such as tensile strength, compression strength, and modulus of elasticity, as well as increasing dimensional stability through reduced sinter shrinkage. In addition, low-temperature sintering can be used to produce parts with improved dimensional accuracy and uniformity by narrowing the sintering range, which reduces warpage and distortion during the cooling process.
Low-temperature sintering can also be used to improve the electrical and optical properties of a component. The process can increase the electrical conductivity of metals used as electronic components by reducing the grain size, eliminating voids, and increasing the contact between grains. In some cases, optical properties can also be improved by reducing the grain size of non-metallic materials and reducing the porosity. The lower sintering temperatures can also be used to reduce absorption of ultraviolet radiation and reduce scattering of visible radiation from the finished component.
In manufacturing processes, low-temperature sintering is particularly attractive since it reduces the energy costs associated with heating and cooling the components during the sintering process. The lower sintering temperature results in faster heating and cooling times, which can result in significant cost savings. Additionally, low-temperature sintering can produce objects with fewer defects and fewer surface imperfections compared to traditional sintering processes. Finally, because of the shorter sintering time and reduced energy costs, many manufacturers are able to reduce the overall processing time, resulting in improved time-to-market for the end product.
Despite its attractive features, low-temperature sintering is not without its drawbacks. The process requires a high degree of part preparation, which can lead to extra cost and time for parts that require unusual geometries. Additionally, because of the lower temperature requirements, it is possible for parts to slowly grow and shrink during the sintering process, creating an issue with dimensional stability.
Overall, low-temperature sintering is the preferred method of powder based fabrication for a number of reasons. It is especially attractive in terms of energy efficiency and cost savings and can provide better mechanical and optical properties than conventional sintering processes. The method will continue to be a mainstay in powder-based manufacturing processes in the years to come.
