The present study examines the effect of trace additions copper (up to 1 wt.%) and zinc (0.5 as alloying elements on microstructure, hardness, wear behaviour T6 treated A356 (Al-7Si) alloy. Wear tests were conducted using a pin-on-disc tribometer under constant sliding speed 200 RPM, varying applied load (20–40 N), distance (0–3000 m) determine rate coefficient friction. results indicated minim...

in the present work, the effect of aluminum content, austenitizing temperature and austempering time and temperature on the mechanical properties and hardness of fe-c-al grey cast iron was investigated. for this purpose, three alloys containing 1, 2 and 4 weight percent of aluminum were provided. the tensile samples were austenitized at 850?c and 900?c for 120 min, followed by austempering proc...

high solid content poly (styrene-co-butyl acrylate) latex ( with 20% and 40% solid content) including high amounts of cloisite 30b (7 wt% and 10 wt%) were kinetically investigated. gravimetric method via measuring the rate of polymerization, number of particles and average number of radicals per particle was used. results showed that by increasing the solid content; the average diameter of poly...

Matrices with very few nonzero entries cannot have large rank. On the other hand matrices without any zero entries can have rank as low as 1. These simple observations lead us to our main question. For matrices over finite fields, what is the relationship between the rank of a matrix and the number of nonzero entries in the matrix? This question motivated a summer research project collaboration...