| Summary: | 碩士 === 國立臺灣大學 === 機械工程學系研究所 === 86 === Endothermic gas is generally used in heat treatment because of its stabl
e quality. However , the preparation time from initial condition to stable
condition is too long. Endothermic gas depends too much on petroleum-based
feedstocks such as natural gas or propane. And the feedstocks are being
used up. Since the ratio of air to fuel feeding into the furnace is fixed
, the ingredients of endothermic gas are fixed. Therefore the range of
the application of endothermic gas is restricted. Characteristics disc
ussed above explain that it is necessary to develop a new method
which can generate atmosphere flexibly for the demand of short-life product
s. A furnace was made for the decomposition of m
ethanol(wood alcohol). Methanol decomposes into CO and H2 when temperature
is over 700℃. Controlled atmosphere was prepared by mixing N2 with gases
which were dissolved from methanol. In addition that atmosphere with consti
tuents similar to endothermic gas was generated, atmosphere with differen
t constituents for different purposes of heat treatment was generated ei
ther. An oxygen probe was used to control the carbon potential of this ki
nd of carburizing atmosphere. According to the experiment , the error of ca
rbon potential control for the atmosphere was within the range of ±0.06%.
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