Surface topography and roughness in hole-making by helical milling

Abstract:A comparison between the geometry of the helical milling specialized tool and conventional end mill was firstly introduced. Furthermore, a mathematical model, in which the cutting area was divided into different cutting zones, was established to simulate the cutting depths and volume of the different cutting edges (three kinds) on specialized tool. Accordingly, a specific ratio between the volume removed by different edges and the total hole volume was derived mathematically and modeled using 3D modeling software SolidWorks. Based on the established models, the cutting depths and cutting volume ratio variation trends under different cutting parameters were analyzed.The results showed that the change rules of cutting depths were different in every cutting zone and influenced greatly by the cutting parameters. In addition, the cutting volume ratio changes with different cutting parameters, but it can only vary in certain range due to the structure of the helical milling specialized tool. The cutting volume ratio obtained from the established model shows a good agreement with the data modeled using SolidWorks, proving that the established model is appropriate. Moreover, the undeformed chip geometry was modeled and observed using SolidWorks. The undeformed chip showed a varying geometry with different cutting parameters and it can be optimized to obtain a good cutting condition during helical milling process.

Section: Cutting Depths Of Periphery Cutting Edge Inside Edge and Oumentioning

confidence: 79%

Section: Introductionmentioning

confidence: 99%

Modeling and analyses of helical milling process

Tian

Liu

Wang

et al. 2016

“…Li et al [14] established a three-dimensions (3D) surface topography simulation model base on an improved Z-map model to simulate the surface finish profile generated after a helical milling operation. A novel dynamic cutting force model is also proposed for helical milling process on the basis of a quantitative description of cutting zones corresponding to helical milling operation, in which the cutting mechanism and the cutting force contribution on both the peripheral and the front cutting edges are taken into consideration simultaneously [15].…”

Section: Introductionmentioning

confidence: 99%

3D FEM simulation of helical milling hole process for titanium alloy Ti-6Al-4V

Qin

et al. 2015

As an emerging hole-machining methodology, helical milling process has become increasingly popular in aeromaterials manufacturing research, especially in areas of aircraft structural parts, dies, and molds manufacturing. Helical milling process is highly demanding due to its complex tool geometry and the progressive material failure on the workpiece. This paper outlines the development of a 3D finite element model for helical milling hole of titanium alloy Ti-6Al-4V using commercial FE code ABAQUS/Explicit. The proposed model simulates the helical milling hole process by taking into account the damage initiation and evolution in the workpiece material. A contact model at the interface between end-mill bit and workpiece has been established and the process parameters specified. Furthermore, a simulation procedure is proposed to simulate different cutting processes with the same failure parameters. With this finite element model, a series of FEAs for machined titanium alloy have been carried out and results compared with laboratory experimental data. The effects of machining parameters on helical milling have been elucidated and the capability and advantage of FE simulation on helical milling process have been well presented.

“…Based on the improved Z-map model, a 3D surface topography model was also developed to simulate the surface finish profile in helical milling processes [20]. Liu et al [21] proposed an analytical model dealing with time domain cutting force, which is a function of helical feed, spindle velocity, axial and radial cutting depth, as well as milling tool geometry.…”

Section: Introductionmentioning

confidence: 99%

Tool life and hole surface integrity studies for hole-making of Ti6Al4V alloy

Zhao

Qin

et al. 2015

Abstract:With a significant growth in use of titanium alloys in aviation manufacturing industry, the key challenge of making high quality holes in aircraft assembly process needs to be addressed. In this work, case studies deploying traditional drilling and helical milling technologies are carried out to investigate the tool life and hole surface integrity for hole-making of titanium alloy. Results show that , the helical milling process leads to much longer tool life, lower cutting force, generally lower hole surface roughness and higher hole subsurface microhardness. In addition, no plastically deformed layer or white layer have been observed in holes produced by helical milling. In contrast, a slightly softened region was always present on the drilled surface. The residual stress distributions within the hole surface, including compressive and tensile residual stress, have also been investigated in detail.