Afield ion atom probe study has been made of a low carbon steel after furnace cooling and rapid quenchingfrom 700°C. Marked segregation of carbon to the boundaries was observed after furnace cooling, but not after rapid quenching. From comparison of previous and present results, it is concluded that the ky value of a steel can be related to the interstitial impurity content (mainly carbon) at the grain boundaries. Heat treatments that, encourage grain boundary segregation of interstitials will result in steels having a high ky value.MSTj1569

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To co-fire with commercial LTCC (Low Temperature Co-fired Ceramic) materials at 850oC ~ 880 oC, different contents of B2O3 were added to the Bi2O3-ZnO-Nb2O5 (BZN) ceramics. The dielectric properties of BZN ceramics sintered at low temperatures were studied. According to the test results, the cubic phase of BZN was transformed into orthorhombic in all the test materials. A BiNbO4 phase was formed in test materials with 2 ~ 5 wt% of B2O3 addition. The BiNbO4 phase was inhibited by extra ZnO addition. The phase transformation of cubic BZN was controlled during the synthesis process of cubic and orthorhombic ZnO-Nb2O5 phase with excess ZnO content. The Cubic and orthorhombic phases of BZN could coexist and be sintered densely at 850 oC/2hr.