6983
In this study , the effects of laser power and scan speed on the relative density , melt pool depth , and Vickers hardness of selectively laser melted ( SLM ) maraging steel were systematically investigated .
 process parameter: laser power; process parameter: scan speed; machanical property: relative density; process parameter: melt pool depth; machanical property: Vickers hardness; enabling technology: laser; manufacturing process: SLM; material: maraging steel
Given options, please tell me the categories of all the listed entity words.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} 
 Entities: laser power, scan speed, relative density, melt pool depth, Vickers hardness, laser, SLM, maraging steel 
Answer:
 process parameter: laser power; process parameter: scan speed; machanical property: relative density; process parameter: melt pool depth; machanical property: Vickers hardness; enabling technology: laser; manufacturing process: SLM; material: maraging steel