Dynamical Characteristics on TRC Test and RRC Test

Abstract

TRC and RRC tests are basic testing methods for studying cold cracking sensitivity of materials. The restraint condition of RRC test is clearly defined but that of TRC test is not. In contrast with this, the testing method of TRC test is much easier than that of RRC test, and an arbitrary loading diagram after weld can be applied in the test.
Therefore, it is very important and useful to clarify the dynamical characteristics of both tests and their corelation.
For this purpose, a series of thermal elastic-plastic analysis by the finite element method was carried out.
The results are summerized as follows.
(1) There is no essential difference between dynamic al characteristics of TRC test and of RRG test if the loading process in TRC test is chosen as similar as the process of development of restraint stress in RRC test.
(2) In TRC test, stress distribution in the throat section may be determined only by the final restraint load, but plastic strain distribution is affected very much by the loading process.
(3) In order to get stress and plastic strain distribution in the throat section, which are very similar to those of RRC test, it is necessary to impose in TRC test a loading process as indicated below,
(a) the load may be applied when heat begins to be transmitted out of the restraint length.
(b) the load may reach at the final value at a temperature which the corresponding RRC test ends.
(c) the final load may be equal to that of RRC test.
(4) The corelation between two tests is obtained as follows,
(a) the free contraction S is measured.
(b) a tensile test is conducted for a weld joint of 2l length.
(c) the elongation of the specimen should be the same as S.