On account of the characteristics of laser double-pass processing,a Nd∶ YAG pulsed laser is chosen as the light source,and a laser time-sharing control system for double-pass outputs is developed.A concrete implemented project for time-sharing spectral technology is put forward,the beam split device is designed to achieve time-sharing beam split,and the time-sharing control circuit is designed to control the device in real time.Then,system program procedure is determined.Finally,laser outputs from different ports in different time are obtained under keeping the output powers.In order to avoid fiber damaging because of the jittering from beam split device,black photographic paper is used to sample of facula.The result shows that the best delay time is 300 ms from changing the holophote position to laser output.This system can not only realize time-share multiplexing and dynamic spectral splitting,but also can satisfy the need of double-pass outputs.Furthermore,the system has a stronger expanding ability,and can provide the convenience for laser improvement and upgrade according to the laser processing condition in reality.

为满足多工位或多工种的激光加工需求,以Nd…YAG脉冲激光器为光源,提出了双工位加工的实施方案,设计出能实时改变激光光路的双工位分光装置,以及能对系统进行控制的系统控制电路,并确定了系统的工作流程及工作时序。最终实现与单工位时等功率输出的双工位系统。为检验实际加工效果,对AZ91D镁合金和3003铝合金分别进行了熔覆和焊接试验,并利用扫描电子显微镜（SEM）和电化学测量系统分别检测熔覆试样的熔覆层与基体结合界面的特征及耐腐蚀性,同时对焊接试样的显微硬度及拉伸性能进行检测。结果表明,熔覆后,熔覆层与基体结合良好,熔覆层组织致密、无裂纹和孔洞,自腐蚀电位比基体提高1.18V,腐蚀电流降低约5个数量级;焊接后,铝合金的硬度变化范围为HV4.927~54,抗拉强度约为母材的82.3%,与单工位加工系统相比,加工效率提高了24.6%,取得了较好的加工效果。

为满足多光路、多工位激光加工需求,采用Nd:YAG脉冲激光器为光源,研制出激光器双光路时分复用系统.提出了时分复用的具体实施方案,设计出能够实现时分复用分光的可控30°旋转分光装置以及对装置的工作状态实现实时控制的时分复用控制电路,并确定了系统的工作时序.最终在不降低输出功率的前提下,实现了激光的时分复用、双光路输出.实验利用能量计采集数据,对光路耦合效率进行计算,实验表明,在电流为50 A、脉宽为4 ms、能量为7.3J时,A路耦合效率为85.21％,B路耦合效率为85.23％,满足多工位加工需求.最后结合实际应用,将所设计的两光路,一路用于焊接,一路用于熔覆.

Longitudinally driven giant magneto-impedance (LDGMI) effect of high frequency is measured for Fe 73 Cu 1Nb 1.5 V 2Si 13.5 B 9 nanocrystalline ribbons annealed under different tensile stress. It can be concluded from the field dependence of phase that imaginary part of permeability μ, which is corresponding to the magnetic losses, plays an important role in the high frequency LDGMI effect, and that the value of transverse magnetic anisotropy field H k can be easily determined by the minimum of the field dependence of phase. It provided a kind of new method to measure the magnetic anisotropy field.