915
The hardness in the weld zone increases and a decrease of hardness is observed along the heat affected zone ( HAZ ) with respect to the base metal as expected .
 machanical property: hardness; concept or principle: weld zone; machanical property: hardness; concept or principle: heat affected zone; concept or principle: HAZ; material: base metal; material: as
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
Answer:
 machanical property: hardness; concept or principle: weld zone; machanical property: hardness; concept or principle: heat affected zone; concept or principle: HAZ; material: base metal; material: as