Porosity is a cavity-like discontinuity and occurs due to the entrapment of gases in the molten weld pool. These entrapped gases don't get a chance to escape from the molten weld pool and hence cause porosity.
<h3>Which discontinuities are caused during welding?</h3>
Weld discontinuities can be defined as "an interruption of the typical structure of a weld, such as a lack of homogeneity in the mechanical, metallurgical or physical characteristics of the weld." Porosity is considered to be the most critical discontinuity. Weld discontinuities include porosity, incomplete fusion, excessive melt.
To learn more about welding visit the link
brainly.com/question/19997700
#SPJ4
Answer: The reasons for African colonisation were mainly economic, political and religious. ... These countries became involved in a race to acquire more territory on the African continent, but this race was open to all European countries. Britain had had some success in halting the slave trade around the shores of Africa.
Spend more time with family.Happiness is the best medicine for events like that