Corrosion-resistant antibacterial copper alloy, and preparation process and application for the same
A corrosion-resistant antibacterial copper alloy includes components having the following contents: B: 0.0035-0.055 wt. %; P: 0.15-0.35 wt. %; Si: 0.005-0.05 wt. %; an unavoidable impurity element with a content less than 0.1 wt. %; and a balance being copper. In the present disclosure, a copper alloy having both high antibacterial and excellent corrosion resistance may be obtained by using the foregoing alloy composition in combination with an improved preparation process. The copper alloy has broad application prospects in complex working conditions such as medical equipment, marine engineering, heat exchange devices or sanitary equipment.
1 . A corrosion-resistant antibacterial copper alloy, comprising components having the following contents: B: 0.0035-0.055 wt. %; P: 0.15-0.35 wt. %; Si: 0.005-0.05 wt. %; an unavoidable impurity element having a content less than 0.1 wt. %; and a balance being copper, wherein
an average grain size of the copper alloy ranges from 4 μm to 7 μm, in the copper alloy, a total proportion of grain boundaries Σ3 and Σ9 satisfies: 60%≤Σ3+Σ9≤75%, and a ratio of a proportion of the grain boundary Σ3 to a proportion of the grain boundary Σ9 ranges from 10.5 to 21.0.
2 . The corrosion-resistant antibacterial copper alloy according to claim 1 , wherein in the copper alloy, a content of B ranges from 0.005 wt. % to 0.015 wt. %; and/or,
a content of P ranges from 0.15 wt. % to 0.25 wt. %; and/or,
a content of Si ranges from 0.015 wt. % to 0.05 wt. %.
3 . The corrosion-resistant antibacterial copper alloy according to claim 1 , wherein in the copper alloy, a content of B ranges from 0.0135 wt. % to 0.015 wt. %; and/or,
a content of P ranges from 0.20 wt. % to 0.25 wt. %; and/or,
a content of Si ranges from 0.015 wt. % to 0.03 wt. %.
4 . The corrosion-resistant antibacterial copper alloy according to claim 1 , wherein the average grain size of the copper alloy ranges from 4.0 μm to 6.0 μm; and/or,
the total proportion of the grain boundaries Σ3 and Σ9 satisfies: 65%≤Σ3+Σ9≤70%; and/or,
the ratio of the proportion of the grain boundary Σ3 to a proportion of the grain boundary Σ9 ranges from 10.5 to 15.
5 . The corrosion-resistant antibacterial copper alloy according to claim 1 , wherein the average grain size of the copper alloy ranges from 5.4 μm to 5.9 μm; and/or,
the total proportion of the grain boundaries Σ3 and Σ9 satisfies: 66%≤Σ3+Σ9≤69%; and/or,
the ratio of the proportion of the grain boundary Σ3 to a proportion of the grain boundary Σ9 ranges from 10.5 to 12.
6 . The corrosion-resistant antibacterial copper alloy according to claim 1 , wherein in the copper alloy, a total content of B and P ranges from 0.155 wt. % to 0.4 wt. %; and/or,
a mass ratio of B to P satisfies: 0.03≤B/P≤0.2; and/or,
a mass ratio of Si to a total mass of B and P satisfies: 0.01≤Si/(B+P)≤0.35.
7 . The corrosion-resistant antibacterial copper alloy according to claim 1 , wherein in the copper alloy, a total content of B and P ranges from 0.20 wt. % to 0.26 wt. %; and/or,
a mass ratio of B to P satisfies: 0.04≤B/P≤0.07; and/or,
a mass ratio of Si to a total mass of B and P satisfies: 0.05≤Si/(B+P)≤0.15.
8 . The corrosion-resistant antibacterial copper alloy according to claim 1 , wherein a 15-minute bactericidal rate of the copper alloy is greater than or equal to 70%; a maximum corrosion depth is less than or equal to 44 μm after 30 days of alternate cold and hot corrosion in a 0.1% formic acid aqueous solution environment; a corrosion weight loss rate is less than or equal to 9.5×10 −5 g/h after exposure to a neutral salt spray environment for 480 h; and duration for resistance to stress corrosion leakage is greater than or equal to 80 days.
9 . The corrosion-resistant antibacterial copper alloy according to claim 8 , wherein the 15-minute bactericidal rate of the copper alloy is greater than or equal to 70%; the maximum corrosion depth is less than or equal to 30 μm after 30 days of alternate cold and hot corrosion in the 0.1% formic acid aqueous solution environment; the corrosion weight loss rate is less than or equal to 6×10 −5 g/h after exposure to the neutral salt spray environment for 480 h; and the duration for resistance to stress corrosion leakage is greater than or equal to 103 days.
10 . The corrosion-resistant antibacterial copper alloy according to claim 1 , wherein an outer surface of the copper alloy further has an oxide film layer.
11 . The corrosion-resistant antibacterial copper alloy according to claim 10 , wherein a thickness of the oxide film layer ranges from 0.20 μm to 0.95 μm; and/or,
the oxide film layer comprises oxides of B, P, and Si, wherein contents of O, B, P, and Si are O: 16-24 wt. %, B: 0.60-0.90 wt. %, P: 0.03-0.05 wt. %, and Si: 0.10-0.13 wt. %, respectively.
12 . The corrosion-resistant antibacterial copper alloy according to claim 11 , wherein a thickness of the oxide film layer ranges from 0.3 μm to 0.8 μm.
13 . The corrosion-resistant antibacterial copper alloy according to claim 10 , wherein a 15-minute bactericidal rate of the copper alloy is greater than or equal to 70%; a maximum corrosion depth is less than or equal to 16 μm after 30 days of alternate cold and hot corrosion in a 0.1% formic acid aqueous solution environment; a corrosion weight loss rate is less than or equal to 5.0×10 −5 g/h after exposure to a neutral salt spray environment for 480 h; and duration for resistance to stress corrosion leakage is greater than or equal to 115 days.