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The microstructure of the SLM 316L SS contains refined sub-grains within each coarse grain and the formation of micro-inclusions i.e .
 microstructure, SLM, SS, grain
Please list all entity words in the text that fit the category. Output format is "word1, 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:
 microstructure, SLM, SS, grain