Surface roughness for TB6 titanium alloy impacts its performance significantly, The effect on surface roughness and defects was studied through face milling parameters, dry milling and tool wear experiment. The results show that surface roughness for TB6 titanium alloy is mostly sensitive to the variation of feed per tooth, the next is the milling width, then is the depth of milling and the last is the milling speed. The VB have a significant influence on surface roughness, especially when VB is greater than 0.2mm, the roughness values increases significantly as well as bringing on some scratches and grooves. Feed mark, smeared and uplift material defects are observed on all machined surface samples. A large number of deposited material or pitting corrosion adhere to the worked surface during dry milling as well as burr formation increasing. Burr formation decreases with the increasing of milling speeds, while increases with the VB increasing. Wherefore, TB6 titanium alloy is suitable for low milling speed with cooling lubrication during milling.

Large deformation and cutting vibration is an important problem in the process of manufacturing ultrathin blade of integral impeller, thus a non-uniform allowance process is used in this paper, which can reduce blade deformation and improve processing quality. Firstly, the influence of concentrated load both on the deformation of thin-walled structure and thickening structure wad analyzed. Then non-uniform allowance machining process of impeller blade was designed. Lastly, tool path was planned and processing experiment was done on the impeller. Results show that the process optimization strategy can effectively reduce milling vibration and milling deformation of ultra-thin blade, the max error optimization rate is 54.47% and the average error optimization rate is 52.57%, which is of significance to the actual production.

After collecting and sorting the domestic and foreign standards, we analyzed the differences between laser additive manufacturing (LAM) and the conventional forging and casting in forming technology, microstructure, defects and the causes, internal quality and mechanical properties. It revealed that compared with conventional forming and casting, the manufacturing cycle of LAM is shorter and the material utilization is higher; the porosity in the blank fabricated by LAM can reach class A1, which is lower than forging class AA. Compared with casting, porosity can reach class B. Yield strength of titanium alloy by LAM in transverse and horizontal are lower than forging and casting by 3.4%, and tensile strength that of forging and casting by 0.78% respectively.

The concept, characteristics of pulse production line is introduced, and the current application of pulse production line is reviewed. The factors influencing pulse production line and the necessity of state prediction are analyzed. Then, a method of state prediction based on Markov chain model is proposed. Based on Markov Chain forecast theory, the running states of pulse production line are classified. The state transition matrix is determined and the Markov forecast model is established. Last, the validity of the model is estimated.

As the complexity of system rising day by day, the idea of system engineering is used in civil aircraft design more and more, and the model based system engineering (MBSE) is the trend. This article described the concept and process of civil aircraft design based on MBSE method and three important standards which bring a lot of benefit to MBSE during its development. Then it listed a few familiar software tools which are wildly used in deferent stages of MBSE process. And it also proposed the tool chain architecture of MBSE which can provide a good reference for making MBSE practicable in civil aircraft design.