An investigation on machinability of nodular cast iron by WEDM

Abstract

In this study, the machinability of standard GGG40 nodular cast iron by WEDM using different parameters (machining voltage, current, wire speed, and pulse duration) was investigated. From the results, the increase in surface roughness and cutting rate clearly follows the trend indicated with increasing discharge energy as a result of an increase of current and pulseon time, because the increased discharge energy will produce larger and deeper discharge craters. Three zones were identified in rough regimes of machining for all samples: decarburized layer, heat affected layer, and bulk metal. High machining efficiency can be obtained when the proper electrical parameters are selected, but whether high energy or the low energy is used, a coarse surface is always obtained. The variation of surface roughness and cutting rate with machining parameters is mathematically modeled by using the regression analysis method.

Investigation on experiment and simulation of the grinding process of cast iron

“…But in the cutting process of cast iron, tool wear is still a prominent problem, which can lead to the poor surface quality. 1–3 In order to reduce the tool wear and improve tool life, the cutting mechanism of cast iron needs to be revealed. In the past, a lot of research work has been carried out to improve the machining performance of cast iron.…”

Ni̇kel Esasli Waspaloy Alaşiminin Tel Erozyon Yöntemi̇yle İşlenmesi̇nde Taguchi̇ Metodu İle Yüzey Pürüzlülüğü İçi̇n Opti̇mum Kesme Parametreleri̇ni̇n Tahmi̇ni̇

“…[6] vurum süresi ve boşalım akımının azalmasına bağlı olarak yüzey pürüzlülüğünün iyileştiğini tespit etmişlerdir. GGG40 sfero döküm malzemesinin WEDM'de kesilmesinde açık devre gerilimi, boşalım akımı ve tel hızındaki artışlar malzemenin kesilme oranında ve yüzey pürüzlülük değerlerinde artışlara sebep olmuştur [7]. AISI 4140 çeliğinin kesilmesinde, malzeme kesilme hızı (kesme süresi) ve yüzey pürüzlülüğü üzerinde en etkili parametre voltaj, en etkisiz parametre ise dielektrik sıvı basıncı olarak belirlenmiştir.…”

Multicriteria Optimization for Determining Low Wear of the Surface Produced in Electrical Discharge Machining

“…However, there are many operating parameters that dictate the quality of the machined feature such as open circuit voltage, discharge voltage, discharge current, current pulse profile, pulse ontime, pulse off time, gap between the workpiece and the tool (spark gap), polarity of tool and workpiece, dielectric medium etc. The various models reported in the literature [1][2][3][4][5] correlating process parameters to surface finish of the machined surface are based on specific ranges of process parameters and particular workpiece -tool combination. The models cannot be used either for different workpiecetool combination or for different ranges of process parameters.…”