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Such structures with designed compositional gradation and tailored thermal properties opens up the possibilities of multi-material metal additive manufacturing for next generation of aerospace structures .
 designed, thermal properties, multi-material, metal additive manufacturing, aerospace
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:
 designed, thermal properties, multi-material, metal additive manufacturing, aerospace