Development of the new fabrication system of dental prostheses using the computer assisted combined machining

利用计算机辅助组合加工开发新型假牙制造系统

• 批准号: 08457535
• 负责人: MIYAZAKI Takashi
• 金额: $ 4.74万
• 依托单位: Showa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08457535/
• 关键词: Titanium; Laser; Welding; NC(数値制御); レーザ; NC; 放電加工; レーザ溶接; +フライス加工; 数値制御; CAD; CAM

In order to reduce labor in the laboratory works and to fabricate prostheses with higher quality we already proposed the numerically controlled combined machining. Welding is a key technology to combine the separated parts fabricated casting, mechanical machining, and electric discharging machining. Therefore, we developed the numerically controlled Nd : YAG laser welder. We remodeled the oscillating battery to control the welding energy using PWM where additional pulse with lower pulse height was applied after the initial pulse to increase welding properties. We shot the single pulse to pure titanium to observe the melting properties. We found internal porosity and rough surface on the specimens since the cooling rate was too fast and molten pond solidified before the wave focused. We also found the room for the available energy to obtain good welding was restricted. On the contrary, we could reduce internal porosity and surface roughness with PWM since the solidification started afte … More r the wave of molten pond focused. In addition, freedom of available energy level increased with PWM and we expected to apply the PWM to numerically controlled welding although we found the higher amount of evaporation and deeper concavity of molten pond. Additionally, we performed the experiments to evaluate the welding shrinkage with PWM.We welded a titanium rod with the diameter of 2 mm on the titanium plate with the thickness of 3 mm and measured the shrinkage at the welding. Shrinkage was 24 mum without PWM and 6 mum with PWM.Metallurgical observation indicated larger contraction stress was produced without PWM since the both bottom and surface of molten pond solidified before the center part of the molten pond. On the contrary, smaller contraction stress and gap but deeper concavity were obtained with PWM since the bottom of the molten pond solidified prior to the surface. These findings indicated energy control with PWM reduced the residual stress at the welding spot and prevented the deformation and the occurrence of welding crack. We successfully applied the numerically controlled welding to fabricate the metal frameworks for bridge on the metal molds. Less

为了减少实验室工作中的劳动力并以更高质量的假体制造假肢，我们已经提出了单独控制的组合机械。焊接是将分离的零件制造铸件，机械加工和电动机机械组合起来的关键技术。因此，我们开发了数值控制的ND：YAG激光焊机。我们对振荡电池进行了重塑，以使用PWM控制焊接能，在初始脉冲之后，将较低的脉冲高度施加较低的脉冲以增加焊接特性。我们将单个脉冲射向纯钛，以观察熔融特性。我们在样品上发现了内部孔隙率和粗糙的表面，因为冷却速率太快了，熔融池在波动之前固化。我们还发现，可用能量获得良好焊接的房间受到限制。相比之下，自从固化开始以来，我们可以降低内部孔隙度和表面粗糙度。此外，PWM的可用能级自由度提高了，我们希望将PWM应用于数值控制的焊接，尽管我们发现熔融池的经济量更高和更深的凹入性。此外，我们进行了实验，以评估PWM的焊接收缩。我们在钛板上焊接了一个直径为2 mm的钛杆，厚度为3 mm，并测量了焊接处的收缩。收缩为24妈妈，没有PWM，而有PWM的6妈妈，甲状腺质观察表明，在没有PWM的情况下产生了较大的收缩应力，因为熔融池的底部和表面都在熔融池中的中心部分固化。相反，由于熔融池塘的底部在表面之前固化，因此使用PWM获得了较小的收缩应力和间隙，但凹陷是更深的凹度。这些发现表明，PWM的能量控制减少了焊接点的残余应力，并防止了焊接裂纹的变形和发生。我们成功地应用了数值控制的焊接，以制造金属模具上的桥梁的金属框架。较少的

项目成果

Lee Won-Sik, Miyazaki Takashi: Clinical Courses of Dental Laboratory Technology I "Application of laser, electroforming, and electric discharge machining to dental laboratory works". Ishiyaku Publishers, INC, 172-180 (1997)

李元植、宫崎隆：牙科实验室技术临床课程 I“激光、电铸和放电加工在牙科实验室工作中的应用”。

李元植・前原聡・直井繁治・宮崎隆: "パルス改良型Ncl:YAGレーザ溶接機を用いた純チタン溶接における基礎的研究" 歯科材料・器械. 16(S30). 106 (1997)

Yuanshi Lee、Satoshi Maehara、Shigeharu Naoi 和 Takashi Miyazaki：“使用脉冲改进 Ncl:YAG 激光焊接机进行纯钛焊接的基础研究”牙科材料和仪器 16(S30)。

前原 聡 他: "省力化を目的としたNd : YAGレーザ溶接装置の歯科技工への応用に関する研究" 歯科材料・器械. 17 (S31)(印刷中). (1998)

Satoshi Maehara 等人：“以节省劳动力为目的的 Nd:YAG 激光焊接设备在牙科技术中的应用研究”，《牙科材料和仪器》17 (S31)（出版中）。

李 元植 他: "パルス改良型Nd : YAGレーザ溶接機を用いた純チタン溶接における基礎的研究" 歯科材料・器械. 16 (S30). 106- (1997)

Yuan-sik Lee 等人：“使用脉冲改进 Nd:YAG 激光焊接机进行纯钛焊接的基础研究”牙科材料和仪器 16 (S30-1997)。

Lee Won-Sik, Maehara Satoshi, Naoi Shigeharu, Miyazaki Takashi: "Basic Students on the welding of titanium using the PWM NdiYAG laser welder" J J DENT Mater. 16(S30). 106 (1997)

Lee Won-Sik、Maehara Satoshi、Naoi Shigeharu、Miyazaki Takashi：“使用 PWM NdiYAG 激光焊机焊接钛的基础学生”J J DENT Mater。