Evaluation of the strength characteristics of non-metallic elements of the air suspension of machines under the influence of negative temperatures and aggressive environments

The operating conditions of non-metallic elements of the air suspension of road vehicles are analyzed. The influence of deicing agents and negative temperatures on non-metallic (rubber) elements of the pneumatic spring is studied. The methods of conducting tests to assess the effect of negative temperatures and aggressive environments on non-metallic elements of the air suspension are described. It is shown that the destruction of the microstructure is caused by the action of reagents on the rubber part of the pneumatic cylinder. Keywords: road vehicles, air suspension, rubber elements, negative temperatures, deicing agent

DEVELOPMENT OF VIBRATION PROTECTIVE TECHNOLOGIES BASED ON THE MR (METALLIC RUBBER) MATERIAL FOR RUSSIAN LOCOMOTIVES

The article describes the use of the elastic-porous damped wire material MR for solving the problems of ensuring vibration safety when creating locomotives of a new generation. Vibration isolators made of MR material for railway diesel generators and the vibration protection system of the driver’s cabin of the TEM-28 locomotive are considered.

Prediction for Constitutive Relationship of Metallic Rubber with Various Parameters by BP Neural Net

Constitutive relationship of metallic rubber was nonlinear. Considering the constitutive relationship’s complication and BP neural net’s good ability to dispose of nonlinearity, it was necessary that constitutive relationship of metallic rubber on basis of BP neural net was studied. In this paper, coefficients of constitutive relationship for metallic rubber were studied and trained by BP neural net for the two conditions, in which shape factor is only various, density and shape factor are both various, and then coefficients of constitutive relationship were obtained. Coefficients from net prediction were compared with coefficients from experimental data fitted, and they had better consistence. It was proved that prediction for constitutive relationship of metallic rubber by BP neural net was reasonable for the two conditions, in which shape factor is only various, density and shape factor are both various.

Research on Vibration-Reduced Characteristics for Dry-Friction Damping Material of Metallic Rubber

Harmonic balancing method has more powerful superiority than other perturbation methods in the respect of solving steady-state response of strong nonlinear system. The amplitude-frequency equation of dry-friction vibration system considering cubic nonlinear displacement under harmonic excitation was derived by harmonic balancing method. Because the effect of even nonlinear term on vibration response of system was not evident, even nonlinear term of elastic restoring force was neglected. The first term coefficient and third term coefficient obtained by static experimental data for constitutive relationship of metallic rubber were substituted into frequency response equation. Amplitude-frequency characteristics curves of vibration response for cubic nonlinear displacement dry-friction system of metallic rubber were obtained. Natural frequencies obtained by computation were compared with natural frequencies by experiment, and the two Natural frequencies consisted with each other. It showed that the method that vibration response for cubic nonlinear displacement dry-friction system of metallic rubber was computed is reasonable.

Parameter Identification for Nonlinear Dry-Friction Structure of Metallic Rubber

In order to reduce workload of parameter identification for nonlinear mechanical model of metallic rubber, in this paper, based on parameters identification method of static experimental curves, experiments were designed, and data were processed, further aimed at hollow cylindrical metallic rubber, nonlinear dry-friction structural element model’ parameters were identified, what’s more, friction coefficient, radial stiffness, axial stiffness, and friction angle of stainless wire under room temperature were obtained. It was proved by simulation that parameters identification method in this paper was effective and accurate. Based on this, errors of simulation were analyzed elaborately.

The Effect of Heat Treatment Technology on Nonlinear Constitutive Relationship of Metallic Rubber

In order to solve technological key problem of metallic rubber in the respect of engineering application, based on porous materials theory, this paper explored the method of nonlinear constitutive relationship constructed, thus in view of the effect of heat treatment technology on nonlinear constitutive relationship of metallic rubber, static experiments are made for seven kinds of tempered metallic rubber and seven kinds of untempered metallic rubber, it was found that each coefficient of nonlinear constitutive relationship of tempered metallic rubber was bigger than that of untempered metallic rubber, and the deformation of tempered metallic rubber was smaller than that of untempered metallic rubber. Lastly it concluded that appropriate heat treatment technology could improve mechanical properties of metallic rubber.