1449
Among common engineering materials , aluminum alloy is the most susceptible to this defect as the solubility of hydrogen in solid and liquid is significantly different .
 material: engineering materials; material: aluminum alloy; concept or principle: defect; material: as; machanical property: solubility
Please list all entity words in the text that fit the category.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} 
Answer:
 material: engineering materials; material: aluminum alloy; concept or principle: defect; material: as; machanical property: solubility