Free-cutting leadless copper alloy with no lead and bismuth

A leadless copper alloy consisting of:

• 58 to 70 wt % of copper (Cu), 0.5 to 2.0 wt % of tin (Sn), 0.1 to 2.0 wt % of silicon (Si), a balance amount of zinc (Zn), and inevitable impurities, and
• 0.04 to 0.20 wt % of phosphorus (P), less than 0.2 wt % of aluminum (Al), less than 0.1 wt % of nickel (Ni) or less than 0.1 wt % of manganese (Mn),
• wherein a sum of contents of tin (Sn) and silicon (Si) is 1.0 wt %≤Sn+Si≤3.0 wt %, wherein the inevitable impurities are selected from the group consisting of iron (Fe), chromium (Cr), selenium (Se), magnesium (Mg), arsenic (As), antimony (Sb), cadmium (Cd), and the combination thereof, wherein the sum of the inevitable impurities are equal to or below 0.5 wt %, and
• wherein the copper alloy comprises a machinability value of 1.41 to 1.98 N·m of torque average values in 4 to 10 mm cutting section after subjecting to a machinability test performed by a machinability testing machine, wherein the machinability test comprises at least one of the following conditions:
• a size of a cutting drill is ϕ8 mm, a rotation speed thereof is 700 rpm, a moving speed thereof is 80 mm/min, a moving distance thereof is 10 mm, a moving direction thereof is a gravity direction, and torque average values (in units of N·m) of 4 to 10 mm cutting section, and
• wherein the copper alloy is prepared with no addition of bismuth and wherein the copper alloy is in a bar shape.