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Problem statement: Currently, in order to suppress intermetallic reaction layer formation during dissimilar metals welding between steel/aluminum alloy, only laser beam welding as selfbrazing technique has been applied. However, TIG welding process might be one of welding process candidate for joining dissimilar metals welding between steel/aluminum alloys due to its capability in joining thin section. In the present study, the feasibility of application of TIG welding process in joining dissimilar metals between steel/aluminum alloy was evaluated. Approach: In order to realize the feasibility of TIG welding process, bead on the steel sheet experiment and dissimilar metals welding experiment was carried out. Results: From bead on the steel sheet experimental results, TIG welding could produce the partial penetration welding in 1 mm thickness steel sheet. In dissimilar metals welding experiment, TIG welding process as a self-brazing technique could successfully join dissimilar metal between steel and aluminum alloy. Moreover, the load resistance of bonded zone of dissimilar metals joints was higher than the load resistance of A1100 aluminum alloy after welding. Conclusion: These results indicated that TIG welding process is feasible to be dissimilar metals welding candidate for joining steel/aluminum alloy.

Injectable biphasic calcium phosphate bone cements (BCPCs) composed of β-tricalcium phosphate (β-TCP) and hydroxyapatite (HA) have been intensively investigated because of their high rate of biodegradation, bioactivity and osteoconductivity, which can be adjusted by changing the ratio between β-TCP and HA phases after setting. The aim of this study was to evaluate the performance of 1 wt% chitosan fiber additive with biphasic calcium phosphate as an injectable bone cement both in vitro and in vivo. In vitro evaluation of compressive strength, degradation rate, morphology, and cell and alkaline phosphatase activities was done by comparison with bone cement without β-TCP. The in vivo results for micro-CT scanning and histological examinations for three groups (control, BCPC and commercial biphasic calcium phosphate granules) were characterized and compared. After the addition of 20 wt% β-TCP to calcium phosphate cement, the initial and final setting times of the sample were 3.92 min and 11.46 min, respectively, which were not significantly different from cement without β-TCP. The degradation time of the BCPC material was longer than that of calcium phosphate cement alone. The healing process was significantly faster for BCPC than for the control and commercial product groups. Therefore, this is the first evidence that BCPC is an attractive option for bone surgery due to its faster stimulation of healing and faster degradation rate.

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Piezoelectric laminate composite has been successfully fabricated as a smart material by a spark plasma sintering process. Fully or nearly fully dense BaTiO 3 /MgO (pre-sintered)/BaTiO 3 , BaTiO 3 /MgO with 10 vol% BaTiO 3 /BaTiO 3 laminates were sintered at 1300 8C with a holding time of 5 min under a pressure of 35 MPa. From EDS analysis, no reaction between BaTiO 3 and MgO layers was observed along the interface. Effects of cycle stress and stress intensity factor on the voltage response of the proposed laminates were investigated for confirmation of a crack detecting capability. The resultant relationship between crack length and voltage response range clearly showed that the proposed laminates have a crack sensing capacity. q