MIM技術現狀及未來發展趨勢研討展示會.pptVIP

A Brief History of MIM What is MIM? How did MIM Begin Ray Wiech, Inventor of MIM Licensee’s Problematic Formulations Secret Proprietary Information Who is MIMA? Viable Process Current Future Worldwide Market Situation The Art of MIMThe MIM Process in Brief What is Feedstock? Mixing Methods Primary Secondary Binders Shrinkage Volume Pelletizing Compression Ratio Screw Designs Check Ring Clearance Feedstock Manufacturing Pre-Alloyed Powder CIP/Master Alloy Elemental Powders Particle Size and Distribution Atomization (Water vs. Gas) Powder Shape Particle Size and Distribution Typical Laboratory Equipment Feedstock Mixer Twin Screw Turbula Dry Mixer Twin Screw Injection Molding The Importance of a Helium Pycnometer in Powder Metal Injection Molding Why Write on this Topic What is a Pycnometer Monitoring Quality using a Pycnometer Use in Manufacturing Feedstock Use in different Manufacturing Steps Molding Debinding Sintering Use of Regrinds Why? A brief Background A MIM manufacturer sintered 316L MIM tensile bars in two furnaces A and B from different manufacturers. These parts failed both the Tensile Elongation Values specified and was caused by improper Injection Molding Fracture Surface of Tensile Bars shows Pre-existing Voids There is a need for a Tool that Detects Flaws in the Green Parts BEFORE they are Sintered. The Tool is a Helium Pycnometer. A Typical Helium Pycnometer Quality System using Pycnometer Density Feedstock Preparation Quality Measure Density of Metal Powders. Measure Density of Different Binders. Calculate Weight Requirement for each Constituent based on the Volume Fraction needed. Mix Feedstock and make Granules. Measure density and flow. Molding Mold design parameters (runner and gate size, gate placement, venting, mold heating or cooling) and molding machine parameters (temperature, pressure, hold time, cushion, screw return speed) affect the part. A part not molded correctly will lead to poor density and /or distortion.