Most of the researchers are focusing to bring automation in mechanical systems. So, current research work presents a mechatronic system called active hydrostatic journal bearing that is a higher demand of fast-growing industrial needs. The objective is to improve the dynamics and static characteristics of hydrostatic journal bearing. To achieve the objective, a feedback servo controlled system is presented. A mathematical model is proposed for newly proposed active hydrostatic journal bearing with servo control. A comparison has been performed between the active hydrostatic journal bearing and traditional/conventional hydrostatic journal bearing under the influence of different dynamic conditions of load, viscosity, speed, and pressure. The results demonstrate that proposed active hydrostatic journal bearing has better performance, including controllability, stability, faster response, higher stiffness as well as better disturbance rejection. To further enhance the performance of proposed active hydrostatic journal bearing, two different control strategies are proposed such as proportional–integral–derivative and intelligent control. The results show that fuzzy logic–based intelligent control has faster response, greater amplitude reduction, and good stiffness against load. So, it shows that role of active lubrication in hydrostatic journal bearing will have potential applications in high load and high speed.

In order to improve the understanding of the dynamic recrystallization (DRX) behaviors of TA15 titanium alloy (Ti-6Al-2Zr-1Mo-1V), a series of experiments were conducted on a TMTS thermal simulator at temperatures of 1173 K, 1203 K, 1223 K, and 1273 K with the strain rates of 0.005 s⁻¹, 0.05 s⁻¹, 0.5 s⁻¹, and 1 s⁻¹. By the regression analysis for conventional hyperbolic sine equation, the activation energy of DRX inα+βtwo-phase region isQS=588.7 Kg/moland inβregion isQD=225.8 Kg/mol, and a dimensionless parameter controlling the stored energy was determined asZ/A=ε˙exp(588.7×103)/RT/6.69×1026inα+βtwo-phase region and asZ/A=ε˙exp(225.8×103)/RT/5.13×1011inβregion. The DRX behaviors of TA15 titanium alloy were proposed on the strength of the experiment results. Finally, the theoretical prediction results of DRX volume fraction were shown to be in agreement with experimental observations.