Manufacturing Technology

BSc INDUSTRIAL ENGINEERING

Materials & Manufacturing Technology

Casting

Casting is a very important process within the automotive industry and Jaguar. It plays a crucial part in the design and engineering of every vehicle jaguar produces. Casting is used within jaguar for making parts of complex shape that would be difficult or uneconomical to make by other methods, such as cutting from solid material.
Although there are several different types of casting the principal of the process always remains the same it is a manufacturing process by which a liquid material such as molten metal or plastic is introduced into a mould, allowed to solidify within the mould, and then ejected or broken out to make a fabricated part.
There are many different types of casting relevant to which metal is being used, the size and scale of the component, the finish required, the complexity of the structure etc. Within this report I will analyse casting methods, there advantages and disadvantages, defects that can take place, and what treatments are available.

Common casting defects and there possible causes;

There are many different types of casting methods used within jaguar, and with all these different methods come different kinds of defects. Defects can be the result of anything within the process from operator error through to a bad mold or environment. Some of the possible defects and there cause are labelled below.

Flash

Fig1. Casting after flash occurred

Possible causes;
 Flask was disturbed while investment was setting.
 Base was removed too soon.
 Flask was allowed to partially dry before de-waxing.
 Incorrect de-waxing or a furnace malfunction.
 Flask burned out and allowed to cool below (500oF (260oC) before casting reheating, flask allowed to cool between de-wax and placement in preheated oven.
 Flask was improperly handled or dropped.
 Speed was set too high on centrifugal casting machine.
 Patterns were placed on

Bibliography: Lecturers notes: Session 2 – Metals and Alloys: heat treatments & mechanical properties 1 Session 3 - Metals and Alloys: heat treatments & mechanical properties 2 Session 12 – Material and manufacturing process Session 14 - Surface treatments Session 16 – Casting Process Session 18 – Influence of manufacturing route Student notes from various lectures Properties of engineering materials by R A Higgins Foundations of materials and engineering science William F. Smith