Medical prosthetic implants, such as hip replacements, are, at present, made of metals such as stainless steel or titanium. Thes
e metals are much stiffer than the bone, giving poor transfer of load into the bone. New composite materials aim for closer stiffness match. One uses a matrix of high-density polyethylene (HDPE) reinforced with particulate hydroxyapatite (HA), the natural mineral in bone. Data for experimental composites are listed below. Thoseforbone andforthebulk materialsinthecomposite are: bone,7 GPa; HDPE, 0.65 GPa; hydroxyapatite, 80 GPa. (a) Plot the upper and lower bounds for the Young’s modulus of HDPEeHA composites against the volume fraction of reinforcement, f (from 0 to 1), together with the experimental data. (b) Which of the bounds is closer to the data for the particulate composite? Usethisboundasaguidetoextrapolatetheexperimentaldatato findthe volume fraction of hydroxyapatite needed to match the modulus of bone. Is this practical?
1)composite is mixture of two different material in suitable volume fraction and to achieve desire properties for target material. 2)in this case data is given for particulate composite and it is mixture of HDPE and HA and matrix is HDPE
Crossing over is a biological occurrence that happens during meiosis when the paired homologs, or chromosomes of the same type, are lined up. Hope this helps :)
