Three factors affecting feed fluidity of MIM stainless steel

Metal powder injection molding (MIM) is the metal powder and organic binder through mixing, granulation particles into mixture, and manufacturing products into specific characters by means of injection molding method, particularly suited to small, precision manufacturing of complex parts, also got quite a lot of recognition and use of precision parts manufacturers, such as powder metallurgy micro gear, MIM auto parts, MIM mobile phone parts, etc., occupies an important position in the field of metal forming today.

The metal powder injection molding process needs to prepare the injection material in advance, which is often called MIM feed, and has relatively harsh requirements on the rheology of the feed. The two most commonly used metal powder injection feeders of MIM technology are iron based feeders (such as Fe2Ni, Fe8Ni) and stainless steel feeders (such as SUS316L, SUS630, 17-4, SUS304, etc.). With the increasing demand for stainless steel products in recent years, the research on stainless steel feeders is rapidly heating up.

Feeding is the first step of metal powder injection molding process, so the feeding characteristics directly affect the parameters of all subsequent metal powder injection molding process and the quality characteristics of finished products. Based on the most commonly used stainless steel, this paper introduces three factors that affect the fluidity of stainless steel feeding in the process parameters of metal powder injection molding：

First, metal powder loading in injection molding process. Powder loading is a ratio, referring to the percentage of metal powder volume in the total volume of feed. The larger the load amount of metal powder, the higher the proportion of metal powder in the feed, the higher the viscosity of the feed, and the change of rheology accordingly. When the loading quantity of metal powder increases, the proportion of binder will increase correspondingly. At this time, the feed viscosity decreases and the fluidity improves. Guangdong dahong new materials to remind you that more binders are not better, and should also consider the amount of binders on other subsequent processes.

Second, shearing rate in metal powder injection molding process. In the process of metal powder injection molding, the stainless steel feeding flows under the high shear rate, so the feeding is heated by the high shear force, and the viscosity decreases after heating, so the flow is strong. On the contrary, when the feed flows at a low shear rate, the heat generated by the lower shear force is slow, the viscosity is not significantly reduced, and the fluidity is relatively poor.

Third, metal powder injection molding process in the temperature. This refers mainly to the injection temperature of metal powder injection molding and the temperature after entering the mold cavity. The influence of temperature is a hot activation process for stainless steel feeding. Temperature affects its fluidity through its influence on the feeding viscosity. As the temperature decreases, the feed viscosity increases, and the fluidity decreases.

The above are the three main factors that affect the fluidity of stainless steel feeding by the metal powder injection molding process. In general, the influence of various factors on the stainless steel feed will follow the above rules, but there are many factors that can influence the liquidity of stainless steel, and in different production conditions of change are also different, so the guangdong macro think various stainless steel products manufacturers in the choose and buy new material, the use of stainless steel feeding should be comprehensive consideration, according to the actual situation will be transferred to a state of optimal work environment.

For more information about powder injection molding technology, please click on guangdong da-hong metal powder injection molding MIM technology.