Geometrical shape and dimension errors and surface roughness of stepped holes in a beryllium bronze-aluminum alloy joint produced by forming reamer

• Published in: International journal of advanced manufacturing technology Vol. 117; no. 9-10; pp. 3029 - 3039
• Main Authors: Li, Chao, Zha, Jun, Chen, Yaolong
• Format: Journal Article
• Language: English
• Published: London Springer London 01.12.2021; Springer Nature B.V
• Subjects: Aluminum alloys; Aluminum base alloys; Beryllium; Beryllium bronzes; CAE) and Design; Computer-Aided Engineering (CAD; Concentricity; Coordinate measuring machines; Cutting parameters; Diameters; Engineering; Geometric accuracy; Industrial and Production Engineering; Machining; Mechanical Engineering; Media Management; Original Article; Process parameters; Reaming; Spindles; Surface properties; Surface roughness; Teeth; Verticality; PCD forming cutter; Beryllium bronze-aluminum alloy; Surface quality; Reaming geometric error
• DOI: 10.1007/s00170-021-07863-0
• ISSN: 0268-3768

The beryllium bronze guide sleeve and the aluminum alloy valve body are assembled to form a beryllium bronze-aluminum alloy stepped hole which requires multiple positioning and tool changes during machining, resulting in lower machining efficiency and accuracy. The geometry error and surface quality of beryllium bronze-aluminum alloy stepped holes after reaming were studied in this research. The geometric error (cylindricity, concentricity and verticality) and diameters of the stepped holes were measured by using a three-coordinate measuring machine. The experimental results show that the PCD forming cutters has high geometric error and diameter stability when reaming beryllium bronze-aluminum alloy stepped holes. Under various cutting parameters, the cylindricity of stepped holes was guaranteed to be within 6μm, and the concentricity of stepped holes was guaranteed to be within 6μm, and verticality of stepped holes was guaranteed to be within 2μm. With the increase of spindle speed and feed per tooth, the diameters of beryllium bronze holes increase while the diameters of aluminum alloy holes decrease and then increase. As the cutting allowance increases, the diameters of the beryllium bronze holes and aluminum alloy holes decrease. The laser confocal microscope and scanning electron microscope were used to detect and analyze the surface quality of beryllium bronze-aluminum alloy stepped holes after reaming. The experimental results show that the surface roughness of the beryllium bronze-aluminum alloy stepped holes reamed by using the PCD forming cutter were less than 0.3μm, and the surface roughness of the beryllium holes were slightly larger than the aluminum holes. The fourth group of experimental parameters (spindle speed 1290r/min, feed per tooth 0.01mm/z, cutting allowance 0.06mm) was selected as the actual processing parameters. There are cavities on the surface of the initial stepped holes before reaming and the cavities basically disappear after reaming, so the surface quality of the beryllium bronze-aluminum alloy stepped holes has been greatly improved.