Materials and Processing of Precise Metallic Mold

The aim of this study was to evaluate the surface roughness of two Ormocer-based resin composites before and after mechanical toothbrushing. The study compared the brands Admira and Definite with composites based on conventional monomer systems (Bis-GMA, Bis-EMA, UEDMA e TEGDMA), Z250 and A110. Eight samples of each material with 4mm in diameter and 2mm in height were prepared using a metallic mold. After 24 hours they were polished and examined with a profilometer for measurement of the initial surface roughness (Ra, mm) before mechanical toothbrushing (30,000 cycles). After toothbrushing, the samples were taken to the profilometer once again to check the final surface roughness. The results were submitted to ANOVA and Tukey test (5%). The Admira composite presented a higher mean of surface roughness before toothbrushing (0.132mm), with a statistical difference from the composite A110 (0.082mm). Definite (0.110mm) and Z250 (0.105mm) composites showed no differences between themselves or among the other composites. No statistical differences were observed after toothbrushing between the composites Definite (0.178mm), Z250 (0.187mm), Admira (0.181mm), and A110 (0.193mm). All composites showed a statistically significant increase in the surface roughness after toothbrushing.

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Grain Refinement Performance of Al Cast Using Machining Chips

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.1444 ◽

2010 ◽

Vol 654-656 ◽

pp. 1444-1447 ◽

Cited By ~ 2

Author(s):

Yoshimi Watanabe ◽

Kenichi Tabushi ◽

Hisashi Sato ◽

Eri Miura-Fujiwara

Keyword(s):

Cooling Rate ◽

Grain Refinement ◽

Nucleation Site ◽

Grain Refiner ◽

Metallic Mold ◽

Refinement Effect

In this study, grain refinement performance of as-cast Al using machining chip of Al instead of the grain refiner is investigated. At first, the machining chips of pure Al are placed in metallic mold. Then, pure Al melt is inserted into the mold with the machining chips. From the microstructure of the as-cast Al using the machining chips, it is found that this machining chip in mold can induce grain refinement of as-cast Al. The increment of the Al chips enhances the grain refinement of the as-cast Al. Moreover, it is shown that preheating the mold can reduce the pore inside as-cast Al using the machining chips. This grain-refinement effect by the machining chips would come from the enhancement of cooling rate and the role of the nucleation site. Therefore, it is concluded that the machining chips of Al can enhance the grain refinement of as-cast Al.

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Development of Metal Resin Concrete for Metallic Mold. 1st Report, Injection Molding for Plastics.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C ◽

10.1299/kikaic.58.2816 ◽

1992 ◽

Vol 58 (553) ◽

pp. 2816-2821

Author(s):

Ikuo TANABE ◽

Yasuhiro YAMADA ◽

Jyunnosuke MIZUTANI

Keyword(s):

Injection Molding ◽

Metallic Mold

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Laser Micromachining of Metallic Mold Inserts for Replication Techniques

MRS Proceedings ◽

10.1557/proc-617-j5.5 ◽

2000 ◽

Vol 617 ◽

Cited By ~ 2

Author(s):

W. Pfleging ◽

A. Meier ◽

T. Hanemann ◽

H. Gruhn ◽

K.-H. Zum Gahr

Keyword(s):

Laser Radiation ◽

Etch Rate ◽

Interface Layer ◽

Oxide Surface ◽

Center Line ◽

Metallic Mold ◽

Reaction Injection Molding ◽

Surface Topographies ◽

Excimer Laser Radiation ◽

Induced Reaction

AbstractThe laser microcaving (LMC) of steel is performed with cw Nd:YAG laser radiation. LMC enables a “clean” patterning process with only a small amount of debris and melt. During LMC the formation of a Ni-enriched interface layer and an oxide surface layer may be observed. The formation of these reaction layers as well as the etch rate and the surface quality strongly depend on the chemical composition of the steel and the process parameters. Surface qualities with an roughness of about Ra(center line average)=300 nm can be realised. The ablation rates are in the range of 106 µm3/s. With excimer laser radiation a further improvement of surface topographies can be achieved via laser planarisation. Mold inserts are manufactured by LMC, and microstructures composed of PMMA are successfully demolded by using the Ultraviolet light induced Reaction Injection Molding (UV-RIM) or Photomolding technique. CE(Capillary Electrophoresis)-Chips made of PMMA are successfully demolded, and the functionality of the CE-Chips is demonstrated.

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Feed Rate Control Using Fuzzy Reasoning for a Mold Polishing Robot

Journal of Robotics and Mechatronics ◽

10.20965/jrm.2006.p0076 ◽

2006 ◽

Vol 18 (1) ◽

pp. 76-82 ◽

Cited By ~ 20

Author(s):

Fusaomi Nagata ◽

◽

Keigo Watanabe ◽

Keyword(s):

Rate Control ◽

Feed Rate ◽

Tangential Velocity ◽

Fuzzy Reasoning ◽

Time Cost ◽

Polishing Process ◽

3D Cad ◽

Location Data ◽

Metallic Mold ◽

Cutter Location Data

Reducing time cost of polishing process is a major issue in metallic mold manufacturing. The feed rate, i.e., tangential velocity, of a polishing robot is generally limited to maintain stable contact with workpieces having a large curvature. We propose a feed rate generator using fuzzy reasoning for polishing robots that regulates the feed rate along free-formed surfaces appropriately. The smaller the curvature of the model designed by a 3D CAD, the larger the distance between two adjacent cutter location data (CL data) steps generated by the main processor of CAM. Therefore, given curvature results in acquiring the distance between two adjacent steps of CL data. We also propose a hybrid position/force controller with the feed rate generator enabling the robot to conduct polishing efficiently. Experiments show promising results.

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