Metallographic Studies of Pack Cyanided Mild Steel Using Cassava Leaves

Abstract

Cassava has been found to contain cyanogenic glucoside, which is hydrolyzed to cyanide as a waste product during cassava processing. This cyanide content is found to vary in the various parts of the cassava plant. Powdered cassava leaf has been utilized to pack cyanide mild steel specimens using BaCO 3 and BaCl 2 as energizers. The microstructures of the treated specimens were examined; these revealed a case formation resulting from the diffusion of C into the specimen. The diffusion proceeded from the case to the core of the specimen with increase in treatment temperature and time. The cutting time of the case-hardened steels was investigated and correlated with pack cyaniding heat treatment. The specimens were found to be more resistant to sectioning with increasing temperature and time.

Indentation size effects in pack carbo-nitrided AISI 8620 steels

“…19 3 46 g of bio-processed wasteþ 400 ml of tap water 4.377 0.22 4 35 g of bio-processed wasteþ400 ml of tap water 4.687 0.23 5 26 g of bio-processed wasteþ 400 ml of tap water 5.117 0.26 6 10 g of bio-processed wasteþ400 ml of tap water 5.62 7 0.28…”

“…The BaCO 3 was added as an energizer to accelerate the formation of carbon monoxide. This provides a source of carbon for carbo-nitriding during the diffusion process [6].…”

“…The method uses dried, cyanide-containing, cassava leaf powder, as a source of carbon and nitrogen. Cassava carbo-nitriding has been achieved using a pack cementation process that can be scaled easily into an industrial process [4][5][6]. However, there is a need to study the effects of cassava-based carbo-nitriding on the mechanical and tribological properties of carbo-nitrided steels.…”

“…Most recently, a cost effective, environmentally-friendly carbonitriding approach has been developed for the improvement of the surface hardness and wear resistance of relatively inexpensive low carbon steels [4][5][6]. The method uses dried, cyanide-containing, cassava leaf powder, as a source of carbon and nitrogen.…”

Development of an Environmentally Friendly in-situ Pack-Cyaniding Technique

“…Pack-cyaniding of mild steel using cassava leaves and the characterization of the case formed have been reported [5,6,7]. The presence of cyanogenic glucoside in cassava plant could be the accumulation of products of catabolism of amino acids [8] or a mechanism for deterring predators [9].…”