Correlation between tool flank wear, force signals and surface integrity when turning bars of Inconel 718 in finishing conditions

Author(s):  
P J. Arrazola ◽  
Ainhara Garay ◽  
Exabier Fernandez ◽  
Koldo Ostolaza
2021 ◽  
Author(s):  
Liang Tan ◽  
Changfeng Yao ◽  
Dinghua Zhang ◽  
Minchao Cui ◽  
Xuehong Shen

Abstract This paper investigates the effects of tool wear on the machined surface integrity characteristics, including the surface roughness, surface topography, residual stress, microhardness and microstructure, during ball-end milling of Inconel 718. Tool wear, tool lifetime, and cutting force are measured. In addition, a two-dimensional finite element-based model is developed to investigate the cutting temperature distribution in the chip–tool–workpiece contact area. Results show that the ball nose end mill achieves tool lifetime of approximately 350 min. The cutting forces increase sharply with a greater tool flank wear width, while the highest cutting temperature has a decreasing tend at a flank wear width of 0.3 mm. Higher tool flank wear width produces larger surface roughness and deteriorative surface topography. A high-amplitude (approximately −700 MPa) and deep layer (approximately 120 mm) of compressive residual stress are induced by a worn tool with 0.3 mm flank wear width. The surface microhardness induced by new tool is larger than that induced by worn tool. Plastic deformation and strain streamlines are observed within 10 mm depth beneath the surface. The results in this paper provide an optimal tool wear criterion which integrates the surface integrity requirements and the tool lifetime for ball-end finish milling of Inconel 718.


Author(s):  
W. Li ◽  
Y. B. Guo ◽  
M. E. Barkey ◽  
C. Guo ◽  
Z. Q. Liu

Tool flank wear during hard milling adversely affects surface integrity and, therefore, fatigue strength of machined components. Surface integrity and machining accuracy deteriorate when tool wear progresses. In this paper, surface integrity and its impact on endurance limit of AISI H13 tool steel (50 ± 1 HRC) by milling using PVD coated tools are studied. The evolutions of surface integrity including surface roughness, microhardness and microstructure were characterized at three levels of tool flank wear (VB = 0, 0.1mm, 0.2mm). At each level of tool flank wear, the effects of cutting speed, feed, and radial depth-of-cut on surface integrity were investigated respectively. Fatigue endurance limits of the machined surfaces at different reliability levels were calculated and correlated with the experimentally determined fatigue life. The good surface finish and significant strain-hardening on the machined surfaces enhance endurance limit, which enables machined components have a fatigue life over 106 cycles.


Author(s):  
W. Li ◽  
Y. B. Guo

Interfacial friction between cutting tool and work material leads to tool wear during machining, which adversely affects surface integrity of machined components. In addition, more energy is expected to be consumed to accommodate higher loading during machining. Dimensional accuracy and repeatability of the workpiece is also hard to guarantee when machining with worn tools. In this paper, surface integrity of AISI H13 samples milled using the PVD coated inserts is studied. Three levels of tool flank wear (VB = 0, 0.1mm, 0.2mm) were used to cut H13 tool steel in the experiment. At each level of flank wear, the effects of cutting speed, feed, and radial depth-of-cut on surface integrity were investigated respectively. Under a diverse combination of milling parameters, the evolution of surface integrity with tool flank wear was analyzed. A novel on-line optical tool inspection system integrated with CNC machining center was used to inspect the evolution of flank wear with milling time in order to monitor tool wear conditions.


Author(s):  
W. Li ◽  
Y. B. Guo ◽  
M. E. Barkey

In machining, the interfacial friction between cutting tool and work material leads to tool wear which is considered a critical factor for surface quality of machined components. Surface integrity and fatigue life of machined components will deteriorate when tool flank wear progresses in machining. Hard milling experiments on AISI H13 tool steel (50 ± 1 HRC) using PVD coated tools with different levels of flank wear were conducted in this study. Surface integrity of the machined components with flank wear VB = 0 mm, 0.1 mm and 0.2 mm was characterized. The effects of cutting speed, feed, and radial depth-of-cut on surface integrity were investigated respectively at the three levels of tool flank wear. In addition, four-point bending fatigue tests were performed on the milled samples at five levels of different flank wear (VB = 0, 0.05, 0.10, 0.15, 0.20 mm) to evaluate the trend of fatigue life evolution with the increased tool flank wear.


2012 ◽  
Vol 723 ◽  
pp. 182-187
Author(s):  
Jin Du ◽  
Zhan Qiang Liu

Tool flank wear has the significant effects on machined surface integrity. The influences of tool flank wear on the cutting forces, surface roughness, microhardness and white layer thickness are investigated in this paper through orthogonal milling experiments. FGH95 powder metallurgy (PM) superalloys are machined with coated cemented carbide tools in the milling experiments. The experiment results show that with the increasing of tool flank wear, cutting force, surface roughness and white layer thickness increase. However, the machined surfaces micro-hardness aggravates with the increase of tool flank wear. It is found that, the machined surface roughness, micro-hardness and white layer increase dramatically especially when the tool flank wear exceeds 0.3mm. A conclusion is then be drawn that, the maximum acceptable tool flank wear land is 0.3mm from the view point of surface integrity when FGH95 PM superalloy is machined with coated cemented carbide tools.


Wear ◽  
2021 ◽  
pp. 203752
Author(s):  
A.R.F. Oliveira ◽  
L.R.R. da Silva ◽  
V. Baldin ◽  
M.P.C. Fonseca ◽  
R.B. Silva ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document