The sensor housing is the important component of sensitive elements to provide the necessary protection. An excellent sensor housing improves the responsive speed of sensitive elements that helps flow to reach elements faster. But more than that, the sensor housing protects the elements. Under the protection, sensitive elements can work even in moisture or corrosion condition. We usually produce sensor housing by CNC machining and MIM (metal injection molding). MIM is a cost-effective way for volume production. As a manufacturer of metal injection molding, Let's see the magic of it.
The material, wall sickness, and precision are the key factors to the sensor housing. It can be made of plastic or metal materials. Metal is used often because sensor housing is primarily worked in thermal or chemical industrial environments. The sensor housing is produced independently for a single component. Sometimes companies require volume production for metal sensor housing. MIM (Metal injection molding) is the preferred manufacturing way for it.
To produce the sensor housing, metal injection molding and CNC machining are the optional methods. Even CNC machining can achieve high precision, it can only produce one part at a time. High cost and time consuming prevent CNC machining to be the preferred producing method. Metal injection molding provides an excellent alternative for sensor housing that can produce volumes of parts by mold. The high precise mold guarantees your needed copied appearance, accurate contour, and compact structure.
The difference between plastic injection molding and metal injection molding is the process of metal powder. The process of metal injection molding includes the following steps.
The polymer binder helps the metal powder to be formed better and will be removed completely in the final step.
The equipment will mix the above powder and binder and melt the binder at an elevated temperature until the metal powder particles are uniformly coated with the binders.
The whole process will be performed in the injection molding machine. The mixing materials will be injected into the mold under high pressure and temperature. Sensor housing will be ejected after cooling.
The way of debonding includes thermal debinding, supercritical fluids debinding, and solvent debinding. Solvent debinding is the most usual method. The process removes as much as a possible binder to prevent furnaces(used in the next step of sintering) from clogging. The debinding process goes through more than one cycle to remove enough binders. And the rest binder will be removed completely during the sintering.
The sintering process will be performed in the furnace. There are many void spaces after binder removal. The heat with high temperature is here to evaporate the rest binder and fuse the metal particles together. Usually, the volume shrinkage of final sensor housing is from 15% to 20%. To keep a ideal size of final sensor housing, engineer should consider the volume shrinkage in mold design.
2fprototypes provides metal injection molding for your sensor housing and other projects. We are experienced in mold manufacturing and compabilities of injection molding. Please feel free to contact us if you are in need.