6429
The critical laser energy density was determined to be 86.8 J/mm3 for Invar 36 and 104.2 J/mm3 for stainless steel 316 L. The present study investigated the effects of set radius of curvature and fiber bundle size on the precision of the radius of curvature during continuous carbon fiber three-dimensional ( 3D ) printing .
 laser energy density, be, Invar, stainless steel, set, fiber bundle, precision, continuous carbon fiber, 3D
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:
 laser energy density, be, Invar, stainless steel, set, fiber bundle, precision, continuous carbon fiber, 3D