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The influence of the sub-nano Ni3P and Cu3P phases on the microstructure, mechanical properties, and strengthening mechanism of Cu–20Pb–5Sn-xP (x = 0,0.05,0.1,0.3,0.5) alloy were discussed under the addition of P to obtain a new Pb–Sn bronze alloy applying for bimetallic cylinder block. The results showed that the tensile strength and hardness of the Pb–Sn bronze alloy increase with the P contents, while the elongation increased first and then decreased. The main strengthen mechanism was that sub-nano Ni3P and Cu3P phases dispersed in the matrix, hindering the movement of dislocations during deformation. Additionally, the grain refinement also contributed to the improvement of mechanical properties. The Ni3P phase is easier to form than the Cu3P phase. And it is easier to combine with the matrix and more stable. The Ni3P and Cu3P phases were studied by using different characterization techniques, such as OM, SEM, EDS, XRD, TEM and First-principles, Phase diagram calculation method. When P is added to the alloy, the Ni3P phase first appears in the alloy, and when the P content increases to more than 0.3 wt%, the Cu3P phase begins to appear. This is because the Ni3P phase is easier to form than the Cu3P phase and is more stable. Only after part of P reacts with Ni dissolved in copper to form Ni3P, the remaining P and Cu can form Cu3P.

Tin-based Babbitt alloys are a widely used bearing bushing material which have good comprehensive properties. However, problems such as high-temperature softening and insufficient bearing capacity occur during their use, so the optimization of tin-based Babbitt alloys has become a research hotspot. In this paper, ZChSnSb11-6 alloy was mainly prepared by the gravity casting method, and different amounts of Zn were added to the alloy (the mass fraction values were 0 wt.%, 0.05 wt.%, 0.1 wt.%, 0.15 wt.%, and 0.2 wt.%, respectively). Through the hardness test, the tensile test, the friction and wear test, and the microstructure observation of the prepared alloy, the influence of Zn on the organization and properties of the ZChSnSb11-6 alloy was analyzed. The results show that the size of the SnSb hard phase changed with the increasing content of Zn. The size of the hard phase of the SnSb tended to increase first and then decrease, and the number of phase particles increased first and then decreased, resulting in changes in performance. Through comparison, it was learned that the addition of Zn can effectively improve the hardness, tensile strength, yield strength, and wear resistance of the alloy, but the elongation rate was reduced. When the Zn content was 0.1 wt.%, the hardness value of the alloy reached the maximum value, 25.82 HB, which increased by 7.3% when compared with the sample without Zn. The hardness of the Zn, 0.15 wt.%, is close to that of the Zn, 0.1 wt.%. Compared to the sample without Zn, the tensile strength and elongation of the alloy were maximized at a Zn content of 0.15 wt.%. Compared to the sample without the Zn, the tensile strength was increased by 21.29%, and the elongation rate was increased by 46%. An analysis showed that the alloy has good comprehensive mechanical properties when the Zn content is 0.15 wt.%.