Papers by Keyword: Hot Wire

Abstract: A thick glass plate was cut by using hot wire. Crack growing was stopped when wire temperature was low. Ligament length decreased with increase in temperature of hot wire and full-cutting was achieved at the temperature of 650°C. The center region in the thickness direction seemed to propagate earlier compared to surfaces regions when the crack propagation was stopped. Finite element thermal stress analysis was carried out. According to distribution of thermal stress inside a glass plate, higher stress was generated in the bottom region at the beginning of the process but occurred in the center region in the later stage as matching with the experimental result.

Abstract: An hot-wire GMAW process is proposed in which the wire is preheated by a TIG arc to enhance the wire melting, and the process is aimed at high efficiency welding with a low level heat input. The welding system is designed, the wire temperature is monitored and the metal transfer and arc behavior is observed. The preheating effect on the wire temperature is analyzed, and the influence of the hot wire on the metal transfer, arc behavior, and the weld formation are analyzed, compared with conventional GMAW. The results show that the preheated wire can significantly enhance the wire melting, and thus several beneficial effects on the GMAW process.

Abstract: To measurement Air speed, there are many methods, for example Hot Wire, Ultrasonic measurement and etc. This method use transistor for measurement. The h_fe of transistor is variable in different Thermo. In flow of air, the h_fe is not equal without flow.

Abstract: Cu has been used as interconnection and lead frame in ULSIs. However, the oxidation and contamination of Cu are not easily avoided. As a result, a thin layer of Cu2O, CuO and carbon contaminations are formed at the Cu surface and these resistances are increased. Therefore, Cu cleaning is necessary. There are some reports to remove Cu oxide layers. Chemical processes such as H2 and NH3 plasma reduction are being investigated [1-5]. These methods have the problem of the plasma damage. Lee et al. proposed Cu oxide reduction using vacuum annealing [6]. However, it seems not suitable for the ULSI process, because the heat-treatment of 400oC is necessary. Therefore, low temperature Cu cleaning without plasma assist is strongly desired. In our previous work, we proposed novel low temperature atomic hydrogen or NH3 decomposed species cleaning generated by heated catalyzer [7,8]. However, in the method it is used 100% hydrogen gas. From the view point of safety, hydrogen gas diluted below explosion limit is preferred to use. In this paper we proposed a novel Cu cleaning method by atomic hydrogen generated on a heated tungsten catalyzer using diluted hydrogen as a cleaning gas.