A new method, namely Metal Powder Extrusion & Stacking Modeling is proposed in this paper based on RP and Metal Injection Molding (MIM) principle. Stainless steel powder and thermoplastic paraffin wax-based binder are used in our experiment. Firstly, feedstock is generated by mixing power and binder in a rotor internal mixer. Then the granular feedstock is put into screw-extruder devices to extruded filament, and accumulating green part at atmospheric status. Finally, green part is thermal defatted and sintered in hydrogen atmosphere to product the sintered parts. The testing results are as follows. The density of our RP product is 73.75%. The average shrinkage rate is 7.51%, 18.00%, and 29.31%, for diameter, thickness and volume respectively. Brinell hardness is HB77.52, while bending strength is 457MPa and tensile strength is 163Mpa. The experimental results verify that our proposed method is promising.
In this paper, ultrasonic vibration is adopted and exerted on injection molding in order to improve plastics’ forming ability, and the impact testing is used to analyze different injection parts’ mechanical properties. On the one hand, experiments prove that ultrasonic vibration can increase polymer’s melt flow rate, decrease melt viscosity, and improve injection flowing in mould cavity. On the other hand, the mechanical tests prove that the ultrasonic vibration can improve plastics’ tensile strength, elastic modulus and other mechanical properties. As a result, a weldless ultrasound-assisted injection molding method is recommended.
With the development of high density, multi-functions, miniaturization and multi-layer on printed circuit board (PCB) design, great challenges have been presented to the miniaturization of drilling on PCB. In order to meet the hole precision, quality and improve the performance, efficiency of mechanical drilling, further research should be done on the cutting state. Kistler high-precision micro-force platform was used in this paper to test and analyze the cutting force, investigate the general laws of micro drilling, and optimize the parameters for HANS PCB drilling machine. Thereby, to improve the efficiency and precision of the drilling, range of processing, and increasing market competitiveness.
Rolling Imprint Lithography is an Enabling Technique for the Mass Production of Ultra-Precision Micro-Structured Surfaces which are Widely Used in High Value Added Optical Products such as Backlight Guides for Display Devices. the Accuracy of the Produced Micro-Structured Surfaces Relies Heavily on the Master Roller of which Quality is Difficult to be Controlled by Traditional Off-Line Measurement Process due to the Large Dimension and Heavy Weight of the Workpiece. this Paper Presents a CCD Based Non-Contact Measurement System to Perform the on-Machine Measurement of the Structure Pattern on Machined Rollers. Instead of Measuring each Single Structure on the Roller, the System is more Focused on the Characterization of the Conformance of the Structure Pattern with the Designer’s Requirement. Low Angle Monochromatic Light is Used to Extract the Structure Pattern on the Machined Roller Using a High Magnification Objective Lens with a High Resolution CCD Sensor. the Image Processing Techniques are then Employed to Characterize the Captured Image Based on the Designed Pattern Structure. the Developed System has been Mounted on a Single-Point Diamond Turning Machine to Measure the Machined Structured Roller, and the Results Indicate that the Developed Measurement System is Able to Perform the on-Machine Measurement and Characterization of the Structure Pattern of the Machined Roller with Sub-Micrometre Accuracy.
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