The Differences Between Sintering and Melting Powdered Metals

March 13, 2020

If you are into the industry of metal fabrication, you might know some processes behind it.

One kind of metal fabrication is powder metallurgy, which is the production of materials or components out of metal powders. Sintering is exclusive to powder metallurgy when it comes to metal fabrication. Melting, on the other hand, is the preparation of the molten metal for casting. Casting is done through pouring molten metal into a mould cavity, keeping the metal cool and later on extracted for final the process.

Sintering and melting don’t particularly share certain similar characteristics. Here are some notable differences between the two.

Process

Sintering can be grouped into three stages. The first stage involves the heating of the material in the furnace at a temperature rate that can create martensitic, crystalline structures. Then, tools like 3D printing lasers and others are used to press the powders together. The next stage entails the addition of some elements like copper powder or cemented carbides to the processed material from the first stage. The final sintering stage involves the application of some liquid and binder additive that will flow into any openings on the material. This stage helps bind the whole final product together.

Melting, on the other hand, begins on patternmaking. A pattern, which is a replica of the casting exterior, is created. The next step is core making, wherein an additional piece of sand or metal will shape the internal form that will make the casting hollow. This additional piece can be removed after the finished casting. Afterwards, moulding is initiated, which forms a cast around the pattern using moulding sand. The melted metal is then poured into mould cavity. The shakeout process will begin once the melted metal solidifies. The final product is then cleaned.

Liquefaction

Sintering uses a combination of heat and pressure to compact and compress the powdered metal for the final material. This process does not need to cross the energy threshold that is required for turning the metallic material into liquid form. With this fact, sintering makes it possible to process materials at low temperatures in the right conditions.

Alternatively, melting will bring the involved material to a certain temperature for it to turn into a liquid from a solid state. Melting ensures that the material has enough thermal energy to make the transition between energy states. So, melting is a process that relies heavily on temperature to make great products.

Uses

Sintering is best used for joining metal particles together. Metals with high melting points can be sintered without any compromises. This process is also suitable if you want to reduce the porosity of a material’s surface.

Melting is also useful for joining two metal particles together. However, it can also be used to reform a metal through changing object properties. Melting can also be used in liquefying a metal alloy to reform it into a new shape or obtain changes on its physical characteristics.

Sintering and melting have their own ways of providing benefits to metal materials. If you have more questions about these two processes, then visit us now at PM Distributors.

Optimized by: Netwizard SEO