Comparative carburization of heat resistant alloys

Conference · Thu Dec 31 04:00:00 EST 1998

OSTI ID:352592

Mimer, R ^[1]; Phaneuf, M W ^[2]

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1. Kubota Metal Corp., Orillia, Ontario (Canada). Fahramet Div.
2. Fibics Inc., Ottawa, Ontario (Canada)

Two high strength, centrifugally cast heat resistant materials were examined under near identical pack carburizing conditions. The first material represented an alloy class which is becoming the most popular for replacement coils in ethylene pyrolysis furnaces due to its large improvement in carburization resistance over HP based alloys. The second material represented the next generation of alloys to be used for this purpose. Additionally, several investigative techniques were employed to illustrate some of the strengths and weaknesses of each technique. A recent advance in microscopy, the focused ion beam microscope (FIB), is highlighted as a possible alternative to the scanning electron microscope (SEM) and the electron probe microanalyzer (EPMA). The FIB microscope provided exceptional new possibilities for examining heat resistant alloys, primarily due to its ability to section samples in situ and its ability to examine uncoated insulating materials, both of which are difficult or impossible for electron microscopes. The next generation heat resistant material displayed remarkable carburization resistance. It was suggested that the improvement may have be due in part to its ability to form a dense Cr{sub 2}O{sub 3} oxide both internally and on the surface.

• OSTI ID: 352592
• Report Number(s): CONF-980316--
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
36 MATERIALS SCIENCE
CARBIDES
CARBURIZATION
CHROMIUM OXIDES
CRACKING
ETHYLENE
FURNACES
HEAT RESISTING ALLOYS
PETROCHEMICAL PLANTS