Abstract: The disclosure provides a modified tin-phosphor bronze alloy and a preparation method thereof. The modified tin-phosphor bronze alloy comprises the following elements in percentage by mass: 4.0-10 wt % of Sn, 0.01-0.3 wt % of P and the balance of Cu and inevitable impurity elements, the average grain size of the modified tin-phosphor bronze alloy is 1-3 ?m, the grain size is in normal distribution, and the standard deviation of the grain size is below 0.8 ?m; the proportion of the total low-CSL grain boundary in the modified tin-phosphor bronze alloy in the whole grain boundary is 66-74%, and in the total low-?CSL grain boundary, the ratio range of (?9+?27)/?3 is (0.12-0.23):1. The modified tin-phosphor bronze alloy of this disclosure enables a finished alloy can give consideration to both tensile strength and excellent bending performance.

Abstract: The disclosure provides a fine-grain tin-phosphor bronze alloy strip and a preparation method thereof. The fine-grain tin-phosphor bronze alloy strip comprises the following elements in percentage by mass: 4.0-10 wt % of Sn, 0.01-0.3 wt % of P and the balance of Cu and inevitable impurity elements, the average grain size of the tin-phosphor bronze alloy strip is 1-3 ?m, the grain size is in normal distribution, and the standard deviation of the grain size is 0.9 ?m or below; the proportion of the total low-?CSL grain boundary in the tin-phosphor bronze alloy strip in the whole grain boundary is 66-74%, and in the total low-?CSL grain boundary, the ratio range of (?9+?27)/?3 is 0.12-0.23:1. The fine-grain tin-phosphor bronze alloy strip of this disclosure enables a finished strip can have the tensile strength and the excellent bending performance at the same time.

Abstract: The disclosure provides a modified tin-phosphor bronze alloy and a preparation method thereof. The modified tin-phosphor bronze alloy comprises the following elements in percentage by mass: 4.0-10 wt % of Sn, 0.01-0.3 wt % of P and the balance of Cu and inevitable impurity elements, the average grain size of the modified tin-phosphor bronze alloy is 1-3 ?m, the grain size is in normal distribution, and the standard deviation of the grain size is below 0.8 ?m; the proportion of the total low-CSL grain boundary in the modified tin-phosphor bronze alloy in the whole grain boundary is 66-74%, and in the total low-?CSL grain boundary, the ratio range of (?9+?27)/?3 is (0.12-0.23):1. The modified tin-phosphor bronze alloy of this disclosure enables a finished alloy can give consideration to both tensile strength and excellent bending performance.