Heat input of welding causes temperature gradient in the steel structure. After welding and along with temperature cooling down, residual stresses appear around the welding zone, cause the welding deformation. Residual stresses are a result of the temperature gradient, restraint intensity and the dependency of material properties on the temperature, such as yield strength, elasticity modulus, and thermal expansion coefficient. Vibratory weld conditioning is a new technology which vibrates the workpiece while welding by vibrator. Its main purpose is to refine grain, relieve residual stress, minish welding deformation and improve the properties of welded joint. Firstly, electro-slag weld was done in the two kinds of vibration condition: 0.3g and 0.6g. Then, the distribution of welding residual stress was measured with blind hole-drilling method. Results show vibratory weld conditioning may relief welding residual stress greatly and σ max is less than 1/2σ s . From metallograph, vibratory weld conditioning can refine the grain effectively. The grain size of 0.6g was smaller than that of 0.3g. While from the measuring values of residual stress, 0.6g's are higher than that of 0.3g's.And also conclude that after finishing welding continuing vibrating a period to increase the inputting energy is benefit to the relief of welding residual stress. 0.IntroductionElectroslag welding (ESW) firstly developed in the early 1950's by Paton, was developing forward at the steady speed all the time and is especially widely used in heavy manufacturing. ESW has great superiority in thick plate structure, composite structure and thick wall vessel etc [1,2] . However, while welding, the large heat inputting associated with the process results in a coarse-grained cast structure with a wide coarse grained region in the heat affected zone (HAZ) and at the same time it results in the high residual stress [3] .Vibratory weld conditioning (VWC) is also called the process that vibrating the workpiece while welding, which is developed based on the vibratory stress relief (VSR). VWC puts the periodical force on the weld and the whole workpiece in the process of welding to improve the quality of the weld [4] . Serial researches founded that VWC can refine the grain effectively and reduce the magnitude of residual stress and the weld deformation. Comparing to the heat stress relief, VWC has the good qualities of less investment, more convenient operation, no pollution and shorter manufacturing period. Relative to VSR, VWC vibrates the workpiece from the beginning to the end of the welding

The existence of residual stresses caused by the welding process is an important reason of cracking and distortion in welded metal structures that may affect the fatigue life and dimensional stability significantly. Heat treatment is one of the traditional methods to relieve the residual stresses. But it is often limited by the manufacturing condition and the size of the structures. In this paper a procedure called vibratory stress relief (VSR) is discussed. VSR is a process to reduce and re-distribute the internal residual stresses of welded structures by means of post-weld mechanical vibration. The effectiveness of VSR on the residual stresses of welded structures, including the drums of hoist machine and thick stainless steel plate are investigated. Parameters of VSR procedure are described in the paper. Residual stresses on weld bead are measured before and after VSR treatment by hole-drilling method and about 30%~50% reduction of residual stresses are observed. The results show that VSR process can reduce the residual stress both middle carbon steel (Q345) and stainless steel (304L) welded structures effectively.

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A new series of functionalized ionic liquids containing ester-group were synthesized through a typical two-step way. The physicochemical properties of the functionalized ionic liquids were studied and the tribological properties of them as lubricants for steel-steel contact were evaluated on an SRV friction and wear tester and compared with the perfluoroalkylpolyether (PFPE), a low-volatility and fluorine containing lubricant, and a conventional ionic liquid, 1-butyl-3-methy imidazolium tetrafluoroborate (LB104), which is nonfunctionalized. Results showed that all the ionic liquids studied in this paper have better lubricities than PFPE as lubricants for steel-steel friction pairs. Functionalized ionic liquids show worse friction reducing abilities at relatively lower loads, which could be ascribed to their higher viscosities, but they always exhibit better anti-wear abilities than LB104. The possible friction mechanisms were discussed.

Due to the importance of the Airborne Equipment Software (AES), much more attentions have been drawn into here. Building a unified, standardized and effective management AES defect knowledge base with these data is a definitely valuable work. In this paper a framework of software quality integrate prediction has been established, which is highly essential to make accurate evaluations on the quality, predictions on the defects, identifications on the fault-prone modules. A framework on how to build an AES knowledge base is proposed, a combination mechanism is proposed by involving machine learning technology and production system, in which, in order to provide the instructions for defect prediction and quality assessment of AES.