Experimental studies were made concerning to the annealing and corrosion of the welded P.V.C. plate of 2 nun in thickness. Effects of radiation to the mechanical properties of these materials were also performd.
Tensile strength of welded P.V.C. is decreased by the corrosion of H
2SO
4 HCl and HNO
3, and is increased gradually with annealing time.
Although tensile strength become maximum by the annealing at about 32 hr., and then decrease gradually at the ascended temperature.
These are regarded as the result of HCI discharge, cross linking, double bonding and main chain cutting with effects of decompositions. And welding strength of P.V.C. was affected by the effect of Co
60 radiation.
This is presumed because of the new chemical compound is formed by the physical and chemical reactions with the effects of molecule mobility and ionization affected by the radiation.
From the results of these experiments, authors have found that, welded specimens of P.V.C. are easier in decomposition than parent material of P.V.C., and then welding temperature of P.V.C. must be used up to 190°C.
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