Experimental Investigation Into the Fracture Toughness of Polyethylene Pipe Material

The mechanical behavior of the recently produced gas pipes material PE100 is investigated and compared to the commonly used material PE80 to determine their relative advantages. The two materials show plastic behavior at room temperature. The fracture toughness of the two materials is experimentally determined using the two common elastic plastic fracture mechanics methods: the ASTM multiple specimen test method for determining the J-R curve of the materials, and the crack opening displacement (COD) method. The investigation of the fracture behavior of the two materials includes the effect of the specimen thickness as well as specimen configuration. The experimental tests were carried on the compact tension (CT) specimens and the single edge notch bending (SENB) specimens. At −70°C, the materials show elastic behavior, the ASTM test method for determining fracture toughness is applied to SENB specimens to determine K_IC of both materials. PE80 shows greater resistance to fracture than PE100.