You are working as an apprentice technician for a large company that manufactures hydraulic systems and airframe components for the aerospace industry. Your training supervisor has reviewed your progress and is impressed by your general understanding of the metallic materials used in the manufacture of the company’s products.
They have now asked you to investigate the microstructure of ferrous and non-ferrous metals and the effects of processes, such as heat treatment and mechanical forming, on the mechanical properties of these materials.
You are going to investigate the micro-structures of a range of metal samples and identify the material and processing history by comparing what you see with reference sources.
To do this:
Your tutor will provide you with a selection of ferrous and non-ferrous specimens that have been prepared for micro-examination and are of known origin (composition and processing history, see the images in the attachment).
You need to:
- Examine the surface of each image (attached below) and make visual records of what you see. These are annotated to identify features of the grain structures such as grain boundaries, impurities, phases (for example, pearlite, and ferrite in steel);
- Compare the surface image against a data source and identify the material and processing history (for example, cold-rolled mild steel will have elongated [distorted] ferrite crystals; cold rolled mild steel followed by annealing will have equiaxed ferrite crystals).
findings of your micro-examinations and consider the effects of processing history and material composition on the mechanical properties of your tested materials, for example, increased hardness caused by cold working or heat treatment.
Your report should include:
- Annotated images of the examined samples (attached below)
- Evidence of identification against the reference source with comparative commentary (micrograph number from websitedoitpoms.ac.UK)
- An annotated phase diagram for each specimen (attached below)
Information about the effect that impurities and grain boundaries have on the mechanical properties of materials
- Explain how the micro-structures of non-processed metallic materials affect the mechanical properties of the materials.
- Explain how the micro-structures of processed metallic materials affect the mechanical properties of the materials.
- Analyze, using an accredited data source, the microstructures of non-processed and processed metallic materials to correctly identify the material, including how the processing history affects the mechanical properties of the materials.
- Evaluate, using an accredited data source, the microstructures of non-processed and processed metallic materials to correctly identify the material, including how the processing history, impurities, and grain boundaries affect the mechanical properties of the materials.