The main materials used for the frame of the adult wheelchair are steel, aluminium and titanium. High performance carbon fibre composites and magnesium alloys are not yet widely available. The price of manual wheelchairs on the market generally depends on the material used for the manual wheelchair, with lighter wheelchairs being relatively more expensive. Steel wheelchairs can weigh up to 22.5kg, aluminium wheelchairs 11.25-13.5kg and titanium wheelchairs can be further reduced to 6.3-9kg at 3-5 times or more the price of titanium wheelchairs steel wheelchairs.

These materials are important because they help to determine quality and can affect the practicality of the chair and the longevity of the wheelchair. Each part of the wheelchair is checked before it is assembled to ensure the highest possible quality.

Steel wheelchairs

Steel is by far the most widely used material in the wheelchair manufacturing industry and has the longest history of use. The steels used for wheelchair skeleton materials are alloy steel, stainless steel and carbon structural steel. Although the technology of steel tubes for adult wheelchairs is quite mature, the wall thickness of steel tubes has been achieved to a satisfactory degree by optimising the composition, advanced heat treatment processes and machining processes, while ensuring performance. The wall thickness of steel tubes used for wheelchair frames is almost close to the limit. Steel wheelchairs are difficult to break through in the face of higher requirements for lighter weight.

Titanium wheelchairs

Titanium alloys are widely used in aerospace, machinery, medical, energy and many other fields because of their light weight, high strength, toughness, resistance to high and low temperatures, non-toxicity and good corrosion resistance. Titanium alloys have a higher specific strength than aluminium and do not corrode in normal environments, so no additional anti-corrosion treatment is required. The main advantages of titanium wheelchairs are their robustness, lightness, comfort, aesthetics and long life. Titanium is mainly used in the wheelchair range, such as basketball wheelchairs and racing wheelchairs. Due to its high price, its use in common wheelchairs is limited. Currently, the application of titanium alloy in adult wheelchairs has no significant advantage in the market due to the high cost and high price of the product.

Magnesium alloy wheelchairs

Magnesium alloy is currently the lightest commercially available metal construction material in the world. Compared with other structural materials, magnesium alloy has a series of advantages: outstanding specific strength and specific stiffness; good casting performance, suitable for high-pressure casting; significant fatigue and no memory; better dynamic characteristics; relative to steel, aluminium and other metal parts, has excellent vibration damping characteristics; good processing properties; easy to recycle. The main problem in making magnesium wheelchairs is the poor corrosion resistance of magnesium alloy as a structural material. Therefore, there are basically no magnesium alloy wheelchairs on the market at present.

Aluminium wheelchairs

The strength of aluminium alloy is the same as steel and its density is 1 / 3 of steel. compared to other materials, aluminium alloy has good lightweight effect, good corrosion resistance, good recycling, easy processing and shaping, mature surface coating and anodising process. Due to the relatively low production cost, perfect process and no need for specialised production equipment and technology, aluminium alloys have become the most desirable and popular material for comprehensive lightweighting performance. They can be heat treated prior to use to improve their performance to meet the needs.

Weight reduction in adult wheelchairs is mainly achieved from a material perspective. Titanium and magnesium alloys have better overall performance than aluminium alloys. However, due to production costs and technical requirements, titanium wheelchairs and magnesium wheelchairs are relatively cheap aluminium alloys. The advantages of wheelchairs are not obvious.

Composite wheelchairs

Composite materials have become one of the hot spots in materials research due to their outstanding advantages such as low density, high specific strength, good corrosion resistance and high fatigue strength. However, high production costs are a major constraint to the widespread use of composites. In addition, the bond strength and fracture toughness of composites are not satisfactory, and the repair of composites is more difficult than that of metallic materials. Therefore a time found that the use of composite materials in wheelchairs is not very common at present.