Analysis of Some Basic Coated MMAW Electrodes Based on Statistical Analysis, Mechanical Weld Properties and Hydrogen Content

Experimental investigations have been carried out to study the behaviour of basic type of coated electrodes (IS:E614514 HJ, AWS: E7018,DIN: E5144B 1026) of different sizes produced by different manufacturers for evaluation of process stability, weldment mechanical properties and diffusible hydrogen content .Time analysis, voltage analysis and current analysis have been carried out using an 'Analyser Hannover'. This is a digital measuring and analyzing system. The time analysis does not indicate any definite trend so results have been interpreted on the basis of voltage and current analysis. The experimental results reveal that the arc stability has no definite trend for the electrodes produces by a particular manufacturer. However, relatively better arc stability is associated with the electrodes of particular manufacturer depending upon the size of electrode. The melting rate (gm/J) increases with the increase in the electrode diameter. The mechanical testing of the weldments indicate that all the electrodes which have been used, confirms to the IS, AWS, ISO and DIN standards i.e. they met the quality and requirement of the code. Higher impact strengths are associated with the electrode which yield low diffusible hydrogen contents.