| Single-layer brazed diamond abrasive tools with optimum grit distribution have some distinguished advantages, such as high grit exposure, large storage space, strong grit retention, high grinding efficiency and high utilization rate of grits. Consequently, the brazed diamond tools show remarkable merits over the conventional electroplated diamond tools in the high efficiency and heavy load machining process of the difficult-to-cut materials. On the other hand, the different diamond tools have their unique advantages and working field. Additionally, they also have some inevitably disadvantageous. From a long-run viewpoint, the brazed tools have an improving and developing space. Based on the former research on the fabrication technology of the diamond tools, including vacuum furnace brazing and induction brazing, and the analysis of the interaction behavior between the laser and the materials as well, the way to develop diamond tools by laser brazing was put forward in this investigation. It could provide a new means to braze diamond grits.The main contents in this paper are as follows:1. Experiment platform for laser brazing has been established to match the laser machining equipment, including inert gas protecting device, temperature measuring and controlling system. Through the platform, the temperature measuring and controlling system for instant response could trace the transient surface temperature of the samples, and laser scan brazing was conducted under the cooperation of the laser equipment and the work pieces. The preparative work is essential to the subsequent brazing experiments.2. The instantaneous temperature on the specimen surface was measured successfully by the experiment platform. Furthermore, depending on the model derived from some simple calculations and conditions, the 3D dynamic simulation on the temperature field of laser brazing was completed satisfactorily. It is very important to optimize the working parameters in the laser brazing.3. By choosing the process parameter according to the optimized scope of parameters acquired previously, laser brazing experiments were carried out with Ni-Cr filler alloy and the brazed diamond tool was accomplished. The new-formed reaction products and the interfacial microstructure under the different conditions have been detected by three-dimensional stereomicroscope, scanning electron microscope (SEM), energy dispersion spectrometer (EDS), and X-ray diffraction (XRD). The results show that Ni-Cr alloy has good soakage to diamond grits, and the grits were held firmly by the chemical bonding. During brazing, Cr atoms segregated to the interface area and reacted with C ones to form carbide Cr3C2, which distributed as flake around the diamond. The special filler alloy realized the wetting and joining of both the diamond grits and steel substrate. Laser Raman spectroscopy (LRS) and SEM were used to detect the heat residual stress, the graphitization effects and the chemical soakage. The result indicates that high bond strength between the filler alloy and the grits without the thermal damage could be reached by applying the optimum induction brazing technique.4. In this work, the diamond grinding wheels with segment structure were firstly prepared successfully by laser brazing at home and abroad. Meanwhile, the machining performance of the brazed diamond tools was evaluated. The result shows that the main wear of the diamond grits was normal. None of the grits in the connecting layer was pulled out from the tools.
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