Since the high density polyethylene(HDPE) is popularly used in areas such as the chemistry

construction and the military project

the types and the conditions for usage are verified. The uniaxial tensile test on the smooth surface specimens and the pattern surface specimens is performed

with different stretching speed and tensile directions. The experiment shows that the yield platform value of the smooth specimens also increases with the increase of the stretching speed

which is under the transversal tension. When the stretching speed is 150 mm/min

the smooth transversal tensile specimen has inconspicuous second yield point

which means that it has better performance on the tension. The rate dependence of the pattern specimens is more obvious and its value is 5.02% under 3 different stretching speed. However

the load the pattern specimens can undertake is lower contrast with the smooth specimens. It is easier for the pattern specimens to be broken than the smooth specimens

and it is also easier for the longitudinal tensile specimens to be broken than the transversal tensile specimens. Consequently

the smooth transversal tensile specimen has better tensile strength.