Material for aluminum alloy screw, and aluminum alloy screw and production method therefor

A material for an aluminum alloy screw comprising:

• Si:
• 0.9 to 1.3 wt %,
• Cu:
• 0.8 to 1.5 wt %,
• Mg:
• 0.8 to 1.2 wt %,
• Cr:
• 0.2 to 0.4 wt %,
• Mn:
• 0.15 to 0.45 wt %,
• Ti:
• 0.005 to 0.05 wt %,
• with a balance being Al and inevitable impurities;
• wherein no cracks occur in a compression test in which a compression ratio is 60% or less.

A material for an aluminum alloy screw comprising:

• Si:
• 0.9 to 1.3 wt %,
• Cu:
• 0.8 to 1.5 wt %,
• Mg:
• 0.8 to 1.2 wt %,
• Cr:
• 0.2 to 0.4 wt %,
• Mn:
• 0.15 to 0.45 wt %,
• Ti:
• 0.005 to 0.05 wt %,
• with a balance being Al and inevitable impurities;
• and
• having tensile properties of 430 MPa or more in tensile strength and 8% or more in elongation at break.

A method for producing an aluminum alloy screw, comprising the steps of:

• a heading process step of subjecting a material for an aluminum alloy screw containing Si:
• 0.9 to 1.3 wt %, Cu:
• 0.8 to 1.5 wt %, Mg:
• 0.8 to 1.2 wt %, Cr:
• 0.2 to 0.4 wt %, Mn:
• 0.15 to 0.45 wt %, Ti:
• 0.005 to 0.05 wt %, with a balance being Al and inevitable impurities to cold heading to form a screw head;
• a heat treatment step of subjecting the material for the aluminum alloy screw to T6 heat treatment;
• and
• a rolling process step of rolling the material for the aluminum alloy screw to form a screw shaft portion.