4130 cromoly steel的机械性能：抗拉强度560Mpa,0.2%屈服强度361Mpa,伸长率28%,弹性模量200E/Gpa,硬度156HB；而7075 T6铝合金的机械性能：抗拉强度524Mpa,0.2%屈服强度455Mpa：伸长率11%,弹性模量71E/Gpa,硬度150HB.所以单就硬度而言,4130 cromoly steel要强些.
