Properties of Ceramic Layer Formed by Centrifugal Thermit Reaction with Silicon Sludge Replacement

Abstract

A ceramic-lined steel pipe has been prepared by the thermit reaction of aluminum-ferric oxide under centrifugal force with the partial replacement of aluminum by the silicon sludge obtained from a semiconductor wafer cutting processing. The ceramic layer on the pipe inner surface consists of the crystalline structures of mainly corundum (-Al 2 O 3 ) and hercynite (FeAl 2 O 4 ). The sludge replacement increases the layer density from 2.9 g/cm 3 to 3.5 g/cm 3 and the hardness from 1450 Hv to 1780 Hv. The amorphous phases of mullite (Al 6 Si 2 O 13 ) formed between the crystalline structures are found to be responsible for a significant improvement of the ceramic layer density.

The Effects of an Unexpected Ceramic Coating Phase at the Head of a Pipe on Joining and Postprocessing of a Ceramic-Lined Composite Pipe

“…This is the expected, most preferred product and is an indication of good separation under centrifugal force. Usually, crystal growth initiation occurs from the innermost layer of the steel substrate (base pipe) in a fine columnar structure toward the center of the pipe and produces a strong metallurgical bond between the metal and intermetallic transition layer 7,12 ; however, according to the current work, phase separation happened completely from region C in Figs. 1 and 5, as other earlier regions were disturbed.…”

“…7,8,[20][21][22][23][24][25][26][27][28][29][30] According to literature, the density of the ceramic layer is about 2.9 g/cm 3 . 12 Generally, the ceramic layer is joined to the base steel by an intermetallic Fe-rich layer. The iron-rich layer and Al 2 O 3 ceramic layers are mechanically interlocked by a mosaic structure.…”

“…The applications of these pipes fall into several fields, including, but not narrowed to, transportation of highly corrosive, high-temperature, and abrasive materials such as coal cinder, mineral powder, cement mortar, molten aluminum, and oilwater mixtures. 3,[7][8][9][10][11][12][13][14][15][16] The ceramic-lined steel pipe produced by the SHS technique has captured the market rapidly. Not only is the quality high and the capabilities wonderful, but also the capability price ratio is higher than of other wearable, antiabrasion, and antiheat pipes, and they weigh less compared to the other wearable, cast alloy steel pipes.…”

High-Performance Ceramic-Lined Composite Pipes with ZrO₂ Additive Prepared by Centrifugal-SHS Process

“…[4][5][6][7] However, the effects of these additives on improvement of fracture toughness of Al 2 O 3 ceramic layer are typically limited due to the brittle nature of Al 2 O 3 ceramics. It is well known that introducing of ne zirconia (ZrO 2 ) particles in Al 2 O 3 matrix results in a large enhancement of basic mechanical properties like exural strength and fracture toughness.…”