Produce Precise, Intricate Components by Merging Multiple Parts Into a Single Unit

<p>MIM combines plastic injection molding and powdered metallurgy to efficiently manufacture precise, complex parts in large quantities, often consolidating multiple components into a single part.</p>

Machine producing feedstock for metal injection molding

Optimim_MIM_Process_Hero.jpg

Metal Injection Molding Process

Speak to an Engineer

<ul><li>Precise and complex parts</li><li>High-density parts</li><li>Greater design freedom</li><li>Customization</li><li>Consistency over large production runs</li><li>Part consolidation</li><li>Reduced assemblies</li><li>Material versatility</li><li>Enhanced mechanical properties</li><li>Faster cycle times</li><li>Tighter tolerances</li><li>Decreased defects</li><li>Cost-Efficiency</li></ul>

Metal Injection Molding is the smart choice for projects that demand:

Benefits

Why Choose

Metal Injection Molding?

<ul><li>Parts less than 100 grams</li><li>Tonnage range: 40T to 110T</li><li>Maximum section thickness generally less than 0.25 inches</li><li>Tolerances +/-0.3% with precision down to +/-0.001 inches</li><li>Annual volumes typically 10,000+ parts per project</li><li>Feedstock produced in-house</li></ul>

Key features of our metal injection molding machines include:

Key Features

A Look At

MIM Key Features

<ul><li>Low Alloy Steels</li><li>Stainless Steels</li><li>Special &amp; Custom Materials</li></ul>

Our range of metal materials that are compatible with MIM includes:

Compatible Materials

Choose Your

MIM Materials

Metal injection molding (MIM) combines the precision of plastic injection molding with the strength of powdered metallurgy to efficiently produce complex metal parts in high volumes. This process allows for the creation of intricate designs, often consolidating multiple components into a single part.

<p>Metal injection molding (MIM) frees designers from the constraints of shaping metals like stainless steel, nickel iron, copper, and titanium. This integration offers greater design freedom and enhances part performance.</p>

Inside the MIM Process

<p>Very fine metal powders are mixed with thermoplastic and wax binders to create a homogeneous, pelletized material that can be injection molded like plastic. This method achieves 95-100% of theoretical density, allowing for ultra-high density and close tolerances in high-production runs, unlike standard powder metallurgy.</p>

Optimim_Extra 7.jpeg

Feedstock

<p>The feedstock is heated and injected into a mold cavity under high pressure, enabling the production of highly complex shapes with shorter cycle times. The resulting component, known as a “green” part, mirrors the final design but is approximately 20% larger to account for shrinkage during the subsequent sintering phase.</p>

Optimim_MIM_process_molding.jpeg

Molding

<p>The debinding process involves a controlled method to remove most of the binders from the “green” part, preparing it for sintering. After debinding, the component is known as a “brown” part, ready for the final step in its production.</p>

Optimim_MIM_process_debinding.jpeg

Debinding

<p>During the sintering process, the fragile “brown” part, held together by a small amount of binder, is subjected to temperatures near the melting point of the material. This step eliminates the remaining binder and finalizes the part’s geometry and strength, resulting in a fully dense and robust component.</p>

Plant employee putting parts into sintering machine

Optimim_MIM_process_sintering.jpeg

Sintering

What Is Metal Injection Molding?

See All Resources

<p>At OptiMIM, a key differentiator is the customizable feedstock, produced in-house. This feedstock is made by combining very fine metal powders with thermoplastic and wax binders in a precise recipe to achieve between 95 and 100% theoretical density and close tolerances over high-production runs.</p><p>Making <a href="/materials" target="_self">metal injection molding materials</a> to achieve higher strength and density sounds great on paper—but that doesn’t even begin to cover all of the problems that can be solved with proprietary feedstock capabilities.</p><p>In this webinar, MetalSolutions series veteran John O’Donnell and OptiMIM Engineering and Tooling Manager Steve LeBlanc will cover the many ways MIM materials can solve common manufacturing problems, including:</p><ul><li>Modifying material to suit project requirements</li><li>Creating custom material to suit project requirements</li><li>Achieving higher strength, density, and durability than with powder metallurgy</li><li>Shortening your supply chain</li><li>Greater design freedom, and more!</li></ul><p><strong>Please fill out the form to download our free on demand webinar.</strong></p>

Optimim_Resources_Webinars.png

Learn how to troubleshoot common issues in MIM projects, from material flow concerns to final part properties, with insights from OptiMIM specialists.

How to Solve Problems with MIM Materials | OptiMIM Webinar

This webinar explores how customizable metal injection molding (MIM) materials can solve manufacturing challenges by enabling higher strength, tailored properties, shorter supply chains, and greater design freedom. 

How to Solve Problems with MIM Materials

<p>Sintering is the crucial final step in the <a href="/metal-injection-molding/process" target="_self">Metal Injection Molding (MIM) process</a>, where "brown parts," which have already undergone debinding, are transformed into solid, finished components. These parts are carefully placed on specialized ceramic trays designed to minimize shifting during the intense heat of the sintering process. The trays are then loaded into a high-temperature furnace where the parts are gradually heated. This controlled heating allows any remaining binder material to evaporate, ensuring a pure and dense final product.</p><p>As the temperature climbs higher within the furnace, it reaches a point where the individual metal particles within the part begin to fuse together. This fusion process, driven by atomic diffusion, solidifies the component and gives it its final strength and form. During sintering, the part typically shrinks by about 20%, a critical factor that engineers must consider during the initial design phase. Once the sintering process is complete, the furnace cools, and the parts are carefully removed. At this stage, they are considered finished, although some parts may undergo additional processing like machining or surface coating to meet specific application requirements.</p><h2>Types of Furnaces</h2><p>There are two kinds of furnaces that are available for MIM production: continuous furnaces and batch furnaces. Continuous furnaces can debind and sinter in the same step. The temperatures reach near melting temperature of the base metal, and these furnaces are only ideal for high volume manufacturing. The batch furnaces also reach temperatures near the melting temperature of the base metal but have a much shorter process time then continuous furnaces. These furnaces run under vacuum and during the process a flow gas is pumped through the furnace – these gases can be nitrogen, argon or hydrogen. There is also supporting equipment for this furnace, including a hydrogen generator, a nitrogen generator, and a back up emergency power generator for cooling the vessel in times of a power failure.</p><h2>Issues During Sintering</h2><p>There are issues that can occur during sintering, which is why the design step of our business is problems with the final part. These problems include not taking into consideration gravity or friction. The resulting part can be warped. There are options that <a href="/additional-capabilities/engineering" target="_self">our engineers</a> use to minimize this. Some of these options include spacers, adding a support rib to the part, and coining. There can also be sag issues with a part. Using special setters that support the pieces most likely to sag upright can solve this issue. Parts can also be set in a special ceramic tray, or they can include a runner.</p><p><strong>Other articles in the series:</strong></p><ul><li><a href="/resources/article/mim-series-part-1" target="_self">MIM Series Part 1</a></li><li><a href="/resources/article/mim-series-part-1" target="_self"></a><a href="/resources/article/mim-series-part-2-feedstock" target="_self">MIM Series Part 2 – Feedstock</a></li><li><a href="/resources/article/mim-series-part-3-compounding" target="_self">MIM Series Part 3 – Compounding</a></li><li><a href="/resources/article/mim-series-part-4-molding" target="_self">MIM Series Part 4 – Molding</a></li><li><a href="/resources/article/mim-series-part-5-debinding" target="_self">MIM Series Part 5 - Debinding</a></li></ul>

Optimim_Resources_Articles.png

Understand how the sintering stage densifies MIM components, improving strength, dimensional accuracy, and final material properties.

MIM Process Series Part 6: Sintering | OptiMIM Article

Sintering, the final step in the MIM process, involves heating "brown parts" in a furnace to remove remaining binder and fuse metal particles, resulting in a dense, solid part with approximately 20% shrinkage. 

MIM Process Series Part 6: Sintering

<p>Manufacturers around the globe are always looking to create better-performing metal components. They want more design freedom without sacrificing cost. When traditional methods of casting no longer make the cut, manufacturers are turning to other molding processes to drive their products forward.</p><p>If you are familiar with powdered metallurgy (PM), you know the parts are formed from metal that is pressed together in a die and then sintered. <a href="/metal-injection-molding/process" target="_self">Metal injection molding (MIM)&nbsp;</a>is a complementary process that also uses metal particles—just much finer— to produce high-density components with three-dimensional design flexibility.</p><h2>How Metal Injection Molding Differs</h2><h3>Materials</h3><p>Powdered metallurgy and metal injection molding utilize the same base powders and both processes allow for the use of custom alloys, however, the key difference in material is particle size. Coarser powders used in PM are widely known and the route to make them are inexpensive. MIM powders are much smaller so the process and energy to make them—in that size range—are more expensive to produce.</p><p>The cost of the powdered metal is a key driver when comparing MIM and PM materials. MIM powders are typically more expensive than PM powders since they are finer (-20 micron vs. +100 micron). However, because of the finer material, MIM produces significantly less porosity.</p><p><em>Did you know? </em> PM achieves all density in the compacting stage (85-92% density) while MIM density comes from sintering—a diffusion bond. (95%+ density)</p><h3>Design Freedom</h3><p>Engineers often confuse MIM and conventional PM given that the two start with powdered metal. PM relies on a high-pressure uniaxial compaction. PM is more suitable for simple shapes that are easily ejected from the die cavity. This is where MIM differs. With MIM, there are very few—if any—geometrical restrictions allowing for three-dimensional design freedom.</p><p><strong> Other </strong><a href="/additional-capabilities/part-improvement" target="_self"><strong>design improvements for MIM components</strong></a><strong> include:</strong></p><ul><li>Part consolidation</li><li>Uniform wall thickness</li><li>Coring and mass reduction</li><li>Holes and slots</li><li>Undercuts</li><li>Threads</li><li>Knurling, letter, and logos</li></ul><table><tbody><tr><td>&nbsp;</td><td><strong>Metal Injection Molding</strong></td><td><p><strong>Powdered Metallugry</strong></p></td></tr><tr><td><strong>Powdered Particle Size</strong></td><td>2-15pm</td><td>50-100pm</td></tr><tr><td><strong>Relative Density</strong></td><td>&gt;95-99%</td><td>92% (Max)</td></tr><tr><td><strong>Wall Thickness</strong></td><td>0.30 -10mm</td><td>2-20mm</td></tr><tr><td><strong>Component Complexity</strong></td><td>High</td><td>Medium</td></tr><tr><td><strong>Weight</strong></td><td>0.01-200g</td><td>1-1,000g</td></tr><tr><td><strong>Tolerance</strong></td><td>0.3-0.5%</td><td>0.1-2.0%</td></tr></tbody></table><h3>Physical Properties</h3><p>While the MIM and PM processes may seem similar, the major differences are found in the final properties of the finished component—mainly the final density. When you use the PM process, the friction between the powder and tooling make the final component non-uniform, while MIM parts are uniform in all directions.</p><p>Additionally, sintering for MIM takes place at much higher temperatures than PM (2350-2500F° vs. 1800-2000F°). The larger PM metal powders combined with lower sintering temperatures inherently cause the final PM component to have lower physical properties making MIM components about two times stronger, with significantly better toughness and fatigue strength. </p><table><tbody><tr><td>&nbsp;</td><td><strong>Metal Injection Molding</strong></td><td><strong>Powdered Metallugry</strong></td></tr><tr><td><p><strong>Elongation</strong></p></td><td>High</td><td>Low</td></tr><tr><td><p><strong>Hardness</strong></p></td><td>High</td><td>Low</td></tr><tr><td><p><strong>Surface Finish</strong></p></td><td>High</td><td>Medium</td></tr><tr><td><p><strong>Production Volumes</strong></p></td><td>High</td><td>High</td></tr><tr><td><p><strong>Range of Materials</strong></p></td><td>High</td><td>High</td></tr><tr><td><p><strong>Cost</strong></p></td><td>Medium</td><td>Low</td></tr></tbody></table><h2>When is Metal Injection Molding the Right Choice?</h2><p><br />Where you add cost for more expensive feedstock and tooling, you realize the savings when it comes to high-density, high-complexity components that cannot be made by any other manufacturing process. PM may be a cost-effective alternative for simple parts but MIM can produce part geometries that eliminate secondary operations which can result in significant cost savings.</p><p>Many of our customers find substantial savings when they combine two or more subcomponents into one single MIM component. Additional savings are found when you consider materials, design, assembly and logistic <a href="/metal-injection-molding/benefits" target="_self">benefits to the MIM process</a>.</p><h3>OptiMIM - Leading Metal Injection Molding Manufacturer</h3><p>On every project, we aim to deliver more consistent parts, more efficiently, at lower costs. At OptiMIur goal is to do away with the expenses associated with secondary processes such as machining, achieving net-shape the first time. So we build molds that are more efficient for high-volume production and put in as much complexity as needed up front to avoid costly machining and secondary operations.</p>

Examine the key differences between MIM and powdered metal processes, including design capabilities, material properties, and cost efficiency.

Comparing Metal Injection Molding & Powdered Metallurgy

Metal Injection Molding (MIM) and Powdered Metallurgy (PM) are both used to produce metal components, but they differ in particle size, density, design flexibility, and physical properties. 

Metal Injection Molding Process

Why Choose

What Is Metal Injection Molding?

Inside the MIM Process

Feedstock

Molding

Debinding

Sintering

BEYOND THE BASICS

Elevate Your Knowledge About OptiMIM Metal Injection Molding

Webinar

Article

Article

Global Reach, Custom Solutions

Explore Other MIM Technologies

Surface Finishes

Part Improvement

Secondary Operations

Interested in starting your MIM journey?