1577
In particular , the alternatively arrangement of fine and coarse grains could generate high hetero-deformation induced ( HDI ) hardening along the scanning direction in the aB-built samples by profuse evolution of geometrically necessary dislocation at the boundaries of each layer .
 grains, hardening, scanning, samples, evolution, dislocation, boundaries, layer
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:
 grains, hardening, scanning, samples, evolution, dislocation, boundaries, layer