The Experimental Investigation of The Effect of Machining Parameters on Burr Formation in Drilling of AISI D2 and AISI D3 Cold Work Steels

Abstract

Bu çalışmada, Bilgisayarlı Sayısal Denetimli (BSD) freze tezgâhında boydan boya delik delme sürecinde değişen işleme parametrelerinin, delik sonu çıkışında çapak oluşumuna etkisi incelenmiştir. Deneysel çalışmalarda; iki farklı sertlikteki soğuk iş takım çeliği (AISI D2, 20 HRC ve AISI D3, 28 HRC), iki farklı çap (Ø 8 mm ve Ø 10 mm) ve dört farklı uzunlukta HSS matkap uçlarıyla delinmiştir. Deneylerde üç farklı kesme hızı (5, 10 ve 15 m/dak) ve üç farklı ilerleme hızı değeri (0.04, 0.05 ve 0.06 mm/dev) değerleri kullanılmıştır. Deney sonuçlarına göre, ilerlemenin artmasına bağlı olarak delik sonu çapak yüksekliğinin azaldığı; delik sayısı, kesme hızı ve malzeme sertliğinin artmasına bağlı olarak da delik sonu çapak yüksekliğinin arttığı tespit edilmiştir.

Experimental investigation of surface roughness, flank wear, chip morphology and cost estimation during machining of hardened AISI 4340 steel with coated carbide insert

“…With feed upto 0.09 mm/rev, surface finish improves due to fact that the uncut chip thickness becomes very small which might give rise to the ploughing (led to material side flow), instead cutting of material at lower feeds relative to higher feeds, as reported by Rech & Moisan (2003) and Bartarya and Choudhury (2012). Nevertheless, more increase in feed, the contact length between the workpiece and the tool increases (Kaplan et al 2014;Hessainia et al 2015) and hence resulting in high thrust force (Nayak & Sehgal 2015) since the cutting tool has to extract more volume of material from the workpiece (Das et al 2016;Bouzid et al (2014b); Aouici et al 2014) thereby more vibration and heat generation ) resulting in high Ra values. The experimental results show that average surface roughness are low at higher depth of cut but at a slower rate for which it can be considered as less affecting parameter for surface roughness in the studied range, which could be used to improve productivity if it would not worsen the surface microstructure.…”

The effects of process parameters on acceleration amplitude in the drilling of cold work tool steels

“…In the soft-annealed delivery condition, the AISI D2 and AISI D3 steels had hardness values of 20 HRC and 28 HRC, respectively. The chemical composition of the workpiece materials (Table 1) were specified by energy dispersive spectroscopy (EDS) analysis and their physical properties are given in Table 2 [7,27]. Workpieces were prepared in dimensions of 152×52×52 mm, and 1 mm of chip was removed in a milling machine from all outer surfaces of the workpieces before the machinability tests in order to prevent the tests from being affected by hardening of the outer surface layers and inclined surfaces.…”

“…The conventional drilling procedure, being economical and easily applicable, is one of the preferred machining methods in the manufacture of various industrial products. When turning and milling operations are compared with drilling operations, the kinematic and dynamic structures are similar, and the chip flow and distribution of cutting temperatures are the same [1]. On the other hand, there are some disadvantages to the drilling operation.…”

“…It is used in deep drawing, pressing, and plastic molds, and in sheets of up to 4 mm thick, it is used in cutting dies. The machinability rating of AISI D3 cold work steel is roughly 25 % that of free machining carbon steel 1018 [7,27]. Drilling of these steels is necessarily limited and difficult due to their high wear resistance, high toughness, and compressive strength properties.…”

“…Measurement of acceleration amplitude is the preferred tool in the analyses of high-frequency vibration [4]. There is an increase in induced vibration amplitude with increasing tool wear in the drilling of cold work steel [1][2][3][4][5][6][7].…”