Abstract
One way to solve the problem of vibration in friction units may be to create antifriction composite materials with the necessary tribological characteristics. It is known that the elastic behavior of titanium nickelide (TiNi) during deformation facilitates the absorption of external loads without plastic deformation. This property can provide its long-term stability in friction units, preventing crack formation and increasing wear resistance. This paper proposes new composite materials based on babbitt alloy with discrete reinforcement by particles of a calcium hydride alloy powder, which exhibits phase stability in the TiNi compound region. The objective was to determine the effect of TiNi reinforcing particles on the tribological characteristics of B83 babbitt based composite materials during friction against a steel counterbody. The aim was also to establish the proportion of filler at which the positive tribological properties of the matrix are preserved, friction stability is improved and wear intensity is reduced. Samples were fabricated using hot pressing and extrusion, adding TiNi particles to the matrix powder mixture. Using X-ray spectral analysis and electron microscopy, the preservation of the equiatomic ratio of titanium to nickel was confirmed and a uniform distribution of TiNi particles in the volume of the matrix alloy was demonstrated. Dry sliding friction tests were conducted at a sliding speed of 0.5 m / s and loads ranging from 1 to 5 MPa. The tribological properties and friction characteristics were evaluated. For additional analysis and visualization of friction stability, density maps of the friction coefficient distribution were constructed. It is demonstrated The effect of discrete TiNi particles on the tribological properties of the composite materials, depending on the reinforcing phase content. Thus, reinforcement with 3 wt.% TiNi particles allows the friction coefficient of the antifriction matrix to be maintained virtually unchanged, while simultaneously increasing wear resistance by 14.5 %. The vibrations reduction and friction stabilization due to the damping properties of TiNi are especially noticeable on the density maps of the distribution of the friction coefficient for the B83 + 3 % TiNi sample at a specific load of 3 MPa.
Funding
1. Russian Science Foundation - 25-29-00980