Materials Technology

The knowledge and competences gained in this course will afford the students the lev erage to practice effectively and safely within a workshop environment. The student should be able to meet the following learning objectives: 1. explain the important properties of various types of materials: metals, ceramics, polymers, and composites; 2. describe the relationships that exist between the structural elements of these materials and their characteristics; 3. explain mechanical strength and failure behaviour of these materials, along with techniques used to improve the mechanical and failure properties in terms of alteration of structural elements; 4. describe the basis for the selection of different materials for specific prosthetic and orthotic applications; 5. discuss the toxicity and safety issues associated with the use of specific materials; 6. describe the occupational health and safety policy and procedures in the workplace; 7. demonstrate proficiency in the use of hand tools and machine tools commonly used in the fabrication of orthopaedic devices.

Identification of materials commonly used in prosthetics and orthotics e. g. (a) Steel and its alloys (b) Nonferrous metals and their alloys, such as aluminium (c) Plastics, thermoforming, thermosetting, composites (d) Wood (e) Leather (f) Plaster of Paris (g) Adhesives and Elastic. Chemical composition and properties of the materials listed above. Plaster of Paris – Powdery Cao4+ H2o, Steel – hard vest, tough, Wood – breakable, dry season, Aluminium and many others, make able, Leather and many others. soft, hide/skin, Plastic – breakable, hand. State the physical properties of the materials such as (a)Metals and alloys (i) Solid at room temperature, (ii) has high melting point, (iii) sliming when cut, (iv) forms alloys. (v) Strong and tough, (vi) can be hammered into shape, (vii) good conductor of heat and electricity. (b) Non-Metals such as Leather, plaster of paris, plastics, adhesives, (i) Low melting and boiling point, (ii) dull in appearance, (iii) brittle (breakable, (iv) poor conductor of electricity. Effect of acid, gases and salts on metals and alloys, non-metals used for prostheses and orthoses. Describe the effect of corrosion on metals for prostheses and orthoses. Difference in textures, permeability strength and weight in non-metals. Uses of metals and alloys in prosthetics and orthotics devices such as calipers, braces and many others. Uses of plastics in prosthetics and orthotics; such as KAFO, AFO, SPLINTS and many others. Uses of wood in prosthetics such as Artificial limb, SACH foot, Knee piece. Uses of leather in prosthetics and orthotics, such as ring padding, knee pad, cuff suspension, orthopaedic shoes and many others. Identification of the sources of the following materials used in Prosthetics and Orthotics. Metals, plastics, wood, leather, plaster of paris (pop), adhesives Identification of the following tools and equipment used in Prosthetics and Orthotics. (a.) Vice to hold materials, b.) Hard saw to cut, c.) Guillotine machine to cut, d.) Sheer machine to cut, e.) Grinding stones/machine, f.) Welding machine, g.) Vacuum machine, h.) Suction machine, i.) Oven, j.) Drill press m/c, k.) Lathe machine, l.) Craftsman carver, m.) Skiving machine. Maintenance of the tools and equipment used in Prosthetics and Orthotics. Identification of METALS materials to make calipers and braces. Identification of LEATHER materials to make Orthopaedic shoes, knee pads and many others. and Identification of LEATHER materials to make plaster cast technique. Identification of thermoplaster materials to mould socket and spaces. Identification of wood materials to carve socket in limbs. Identification of foam (pedilene) materials to make extension in devices for cosmetic light finish. Identification of adhesives materials to form wood, leather plastic and many others.