Effect of properties of high-density polyethylene on durability of welded joints
Tóm tắt
The molecular characteristics of pipe grades of high-density and medium-density polyethylene modified by 1-butene do not affect the durability of welded joints. Their long-term strength depends mainly on the density of the base grade of polyethylene and increases by an order of magnitude when the density is reduced in the investigated range. We have obtained mathematical models approximating the dependence of the durability of welded joints on the most important factors: the degree of crystallinity of the polyethylene and the initial stress in the “brittle” and mixed “brittle”-plastic fracture region. The models obtained may be used to assess the quality of the stabilizing system and the effectiveness of the comonomers of ethylene.
Tài liệu tham khảo
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