MIM Vs. Machining

Metal injection molding is a process that combines plastic injection molding and powdered metallurgy. It produces precise, complex metal parts, including stainless steel and other low alloy steels, often in large quantities. Machining, which removes unwanted material from a metal block, offers similar alloy options but may be less cost-effective for complex parts. Before MIM, machining was the primary option for non-castable parts.

Differences Between Metal Injection Molding and Machining

When it comes to similarities, MIM tends to correlate well with machined parts in regards to finished components. Typically, MIM components can be used in the same way as machined parts—aerospace, medical, firearms—and in some cases, MIM parts look very similar to machined parts. However, when it comes down to it, metal injection molding offers advantages for precision components that machining does not solve.

Unique Geometry

MIM offers unique geometry and complexity capabilities. Machining provides limited intricacy, flexibility, and design freedom and often times it is harder to machine complex components. As the components become more complex, MIM becomes more cost effective because the more complex your part, the more machine time it will take to create it.

Strength & Performance

While both processes yield strong parts, MIM components do not endure machine induced stress or internal pressure which may result in deformation over time and potential part failure. MIM parts are molded using conventional molding machines and then are put into an oven where the wax is strategically melted from the component leaving a strong, solid component.

Mold Investment

When creating a MIM component, the complexity of the part is usually tied to the mold investment. Meaning that it is the mold or tool itself that is complex, so you have one upfront cost tied to the complexity of your component. With machining, if you add complexity you are adding extra cost and process time to the part price.

Material Scrap

Material scrap is not wasted with the MIM process. This is important because as a customer if you are sourcing a machined part, you are paying for that scrap. Through the MIM process, you do not have to spend dollars that could be used elsewhere.

Capacity

MIM is more scalable on ramp up capacity. Machining takes a fair amount of time to produce complex parts, so if you want to go to go from 10k parts a week to 20k you have to buy more CNC machines to get up to capacity. With MIM you do not have to do that.

Other Metal Injection Molding Benefits

When you utilize the MIM process, you also get:

• Repeatability
• Improved cycle time
• Part consolidation
• Reduced need for secondary operations

Why Should You Choose MIM Over Machining?

MIM becomes a more cost effective alternative for some applications compared to machining when you consider the volume and complexity of your project. MIM produces complex, net shape components that require no secondary machining requirements. When put to the right application, MIM can significantly decrease costs associated with secondary overhead all while increasing production rates.

Our team of engineers offer design solutions for a variety of industries including consumer electronics, automotive, healthcare, and more. When our engineers are involved early in the project, they can help design a tool and part specifically for mass production. Contact our team today to get started on your next project.