Process cycle of Mild Steel

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Process cycle of Mild Steel
Name
Institutional Affiliation
Process Cycle of Mild Steel

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Introduction
Heat treatment is a process of exposing metal in solid state to more
temperature cycles to obtain desired characteristics. The common type of heat
treatment includes hardening, tempering, annealing, and case hardening, us-
tempering and normalizing. Hardening process induces hardness property
(materialistic phase) to the metal rod. Tempering process soften and improves the
ductility of the metal stress relief reducing the brittleness and making the mild
steel tough to resist fatigue and shock (Fadara D. A., 2011). Case hardening
hardens the surface of the metal and not the core section part. The case hardening
types includes nitriding, carburizing, cyaniding and carbon-nitriding. Reactivity
and nature of carbon affects the mechanical properties and resistance of the mild
steel. Failure of the mild steel in the applications in bridges, building
reinforcement causes collapsing. The report concentrates on carburizing which is
a form of case hardening which involves adding carbon to the surface of mild
carbon.
Objectives
The main aim for the study were;
i. To determine the impacts of heat treatment to mechanical
properties of mild steel.
ii. To determine the most appropriate quenchant.
Material requirements

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The sample of cylindrical mild steel rod with the following measurements,
upper diameter of 36mm, lower diameter of 26mm,length of 95mm and 61mm
length of the thinner part as shown below (Adetunji O. R., 2011).
Figure 1.Dimensions of mild steel (S355JO)
Carburizing materials prepared from a mixture of barium carbonate mixed with
charcoal in the ratio of 2:3 respectively.
Methods
The water quenching method was used. Four specimen were placed in a
crucible and then put to the furnace. The furnace was then heated by use of oil as
a source of fuel to a temperature of 950 oc for about 40 minutes. After the 40
minutes of soaking, the specimen are taken out and placed into cold water for
cooling by the process known as Quenching. When the pieces and the quenching
medium reaches ambient temperature, then they are taken out and eviscerated by
use of the napkin (S. G. Hong, 2010).
The case-hardening process is achieved by placing the specimens in a
stainless cup preventing crucible from carburizing along with the spacimens.The
materials used for carburizing (charcoal and barium carbonate) were put directly
to the specimen, thus reducing them. The stainless cup then put to the crucible in