Strength-weight ratio

Titanium is not a rare element it is the most abundant transition metal after iron, and is widely distributed in the earth s surface, mainly as the dioxide TiOj and ilmenite FeTi03. It has become of commercial importance since World War II mainly because of its high strength-weight ratio (use in aircraft, especially supersonic), its... 

Table 10.2 shows that alloys based on aluminium, magnesium and titanium may have better stiffness/weight and strength/weight ratios than steel. Not only that they... 

Aircraft radomes, ducting, spinners and other parts are often prepared from polyester resins in conjunction with glass cloth or mat. The principal virtue here is the high strength/weight ratio possible, particularly when glass cloth is used. Land, sea and air transport applications account for almost half the polyester resin produced. 

It is widely perceived that carbon nanotubes will allow construction of composites with extraordinary strength weight ratios, due to the inherent strength of the nanotubes. Several rules of thumb have been developed in the study of fiber/matrix composites. Close inspection of these shows that carbon nanotubes satisfy several criteria, but that others remain untested (and therefore unsatisfied to date). High-strength com-... 

Gradient across component thickness No. of cycles—high to low No. of cycles—freeze-thaw Solar gain, surface air flow Liquid, moisture, and/or vapor tightness Strength-weight ratios—relative significance Service environment ... 

Excellent strength and machinability, limited corrosion resistance. Used for components requiring high strength/weight ratio, e.g. truck trailer panels, aircraft structure parts. 

When heat treated and aged have a very high strength. Used principally for aircraft structures, mobile equipment, and equipment requiring high strength/weight ratio. 

Among the refractory metals, perhaps none are as widely exploited for commercial applications as titanium. From golf clubs to shavers, titanium is now pervasive throughout our modern world. Although some of the proposed applications may be suitably classified as hype, the broad appeal for titanium alloys is due to its favorable properties such as high strength/weight ratio and superior corrosion resistance. Titanium is also readily available from a number of mineral sources it is the sixth most abundant metal, behind Al, Fe, Cu, Zn, and Mg. 

Foamed composites are lightweight materials reinforced by fibers. Some of the advantages of these materials are excellent strength/weight ratios, workability, excellent corrosion resistance, and design flexibility of molded products. 

Figure 4-13. Aluminum alloys are used for low density and high strength-weight ratio.

Titanium alloys comprise low- and high-strength materials with low density and high strength-weight ratio. The process industry uses a limited number of titanium alloys chiefly for their corrosion resistance. See Figure 4-14. 

Use of dissimilar metals such as aluminum and carbons steel can result in galvanic corrosion. The entire HMMWV vehicle is secured with more than 2800 rivets, and this design affords the vehicle high-strength-weight ratio each rivet is a preferential site for corrosion. 

When a resin or heavy filler is replaced with the microspheres, most physical properties are reduced, based on constant volume (lower density). Stiffness is reduced, due to the resilient characteristics. Strength/weight ratio, fatigue, stress and resilience can offer useful product enhancement, with relatively small additions. 

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