中文摘要：

基于“光束中空，光内送粉”的专利技术，采用新型光内同轴送粉装置，在45#钢基体上进行变径回转体堆积。分别对变径回转体斜度、Z轴增量及功率进行控制，并分析各自的影响：斜面堆积中倾斜角度与偏移量、扫描速度成正相关，与送粉速度和粉末利用率成负相关，极限倾斜角度与偏移量成正相关，与熔覆层高度成负相关；随着堆积的进行，粉末利用率降低，离焦量变大；在高层熔覆堆积过程中，熔池由三维散热变为二维散热，散热降低，熔池温度上升，应相应减小功率。得到的成型件外观光滑、粗糙度低、成型质量较高，为变截面的三维堆积试验提供参考。

英文摘要：

Based on the patent technology of ＂hollow laser beam and internal powder feeding＂, the accumulation experiments of the reducing solid of revolution are carried out on the substrate of 45# steel with a novel device of coaxial inside-beam powder feeding. In the experiment, we respectively control the axially symmetrical rake, Z axis incremental and power, and analyze their respective influence. The conclusions are as follows.. In the inclined wall depositing process, the skew angle is in direct ratio to offset and scanning rate and is inversely proportional to powder delivery rate and powder utilization ratio. The limit skew angle is in direct ratio to the offset and is inversely proportional to the height of the cladding layer. With the cladding layers increasing, the utilization rate of the powder is reduced and the defocus distance becomes bigger. In the process of high-rise cladding accumulation, molten pool changes from 3D cooling into 2D heat dissipation and formed pool temperature arises, and so the power rate should be reduced correspondingly. The quality of molding parts that this experiment gets finally is higher with smooth appearance and lower roughness. It can provide reference to the test of the variable cross-section 3D accumulation.