Sage Journals: Discover world-class research

Abstract

In this study, the effects of strontium (Sr) and magnesium (Mg) elements in certain rates added to Al-9Si alloy manufactured using permanent mold casting technique on the structural, mechanical, and machinability properties of these alloys were investigated. While microstructural images of the alloys were obtained with an optical microscope, hardness, tensile strength, and elongation to fracture were determined by conventional methods. The resultant cutting force (F) and average surface roughness (Ra) were measured as experimental outputs in the turning process. It was observed that Al-9Si alloy comprised of α-Al, eutectic Al-Si, β, and primary Si phases. The addition of Sr to the Al-9Si alloy led to the formation of the Al₄Sr phase and the transformation of the β phase into the δ phase. The addition of Mg to Al-9Si-0.1Sr alloy caused the δ phase to transform into the π phase. The hardness of the tested alloy increased significantly with the Mg addition. The yield strength and tensile strength of them increased with both Sr and Mg additions. On the other hand, elongation to fracture value of the Al-9Si alloy increased with Sr addition while it decreased with the Mg addition. The F and Ra values obtained from the Al-9Si alloy increased with Sr addition in the turning process while decreased with Mg addition. The results obtained from turning tests were discussed based on the mechanical properties of alloys.

Keywords

Al-Si alloys microstructure mechanical properties cutting force surface roughness

Highlights

Sr and Mg additions in certain rates improve strength of Al-9Si alloy.

Cutting force, surface roughness, built-up edge and built-up layer formation are closely related to the ductility of the Al-9Si based alloys.

Adhesion and wear marks on the machined surfaces of Al-9Si based alloys vary according to the alloying elements.

Introduction

Reducing product weights in the automotive, defense, and aviation industries is crucial for increasing energy efficiency or fuel economy. Al-Si alloys have become important alternative materials for products manufactured in these industries and they are successfully used in the manufacturing of internal combustion engines, electric rotors, jet engines, pump bodies, cylinder heads, pistons, gearboxes, some parts in applications requiring high pressure and corrosion, bushings, shaft bearings, crankcases, and motor vehicles chassis since they have low density, high specific strength, and easy casting.^1,2 Industrial Al-Si alloys have a wide range of chemical compositions and therefore they exhibit different mechanical properties.³ Primarily, the change in silicon (Si) ratio significantly affects the hardness and mechanical properties of binary Al-Si alloys. It has been reported that hardness of the binary Al-Si alloys increases continuously with increasing Si ratio, but their mechanical properties improve up to certain Si rates.⁴ The increase in hardness with increasing Si ratio is based on the increase in the ratio of hard Si particles in their microstructure.⁴ Al-Si alloys exhibit maximum tensile strength and elongation to fracture values in case of they contain 9 wt.% Si.⁴ The decrease in their strength after 9 wt.% Si ratios is due to the increased cracking tendency caused by the growth of primary Si particles in their microstructure.⁴ In addition to the suitable Si ratio, some alloying element additions such as Sr, Mg, copper (Cu), manganese (Mn), zinc (Zn), boron (B), sodium (Na), titanium (Ti), vanadium (V), etc. positively affect hardness and strength properties of Al-Si alloys.^5–13 Cu, Mn, Mg, and Zn additions cause the improvement of mechanical properties due to the solid solution hardening mechanism and/or secondary phase precipitation, Sr, B, Na, Ti, and V grain refinement mechanism. In a recent study,¹⁴ it was revealed that the hardness and mechanical properties of binary Al-9Si alloy produced with permanent mold casting method can be improved even more with 0.1wt.% Sr and/or 0.1wt.% Sr + 0.6wt.% Mg additions, and presented new ternary Al-9Si-0.1Sr and quaternary Al-9Si-0.1Sr-0.6Mg alloys produced with this casting method. Most of the materials produced by casting are subjected to machining in order to be used as final product in mechanical systems. The parameters that affect the product quality or the machinability properties of the material in machining are the cutting speed, feed rate, and depth of cut. Machinability properties are generally determined by F, Ra, and cutting tool wear. These properties have an impact on the product service life. In some recent studies about the machining of Al-Si based alloys have been identified in the literature. Tool wear and Ra increase due to high amount of hard Si particles,¹⁵ Basavakumar et al.¹⁶ and Bayraktar and Afyon¹⁷ determined that built up edge (BUE) consisted of by welding the material to the cutting edge due to friction and pressure between the cutting tool and the workpiece. Zhang et al.¹⁸ found that the cutting stability of Al-Si based alloys increased with Si content in the range of 12wt.%–18wt.% by weight and decreased by 25 wt.% Si by weight, and that the chip breakability increased with increasing of Si content and cutting speed. Kamiya et al. observed that the chip breakability and surface quality increased due to the increase in Si content in eutectic compositions, while tool life decreased. It has been determined that breakability of the chip increases even more, while the surface quality and tool life decrease with increasing of Si content in hypereutectic compositions,¹⁹ Dos Santos et al.²⁰ stated that more feed force was measured compared to uncoated cutting tools in turning of Al-Si alloys containing 12 and 16 wt.% Si with DLC (Diamond-like carbon) coated cemented carbide cutting tool and the highest feed force was measured for both cutting tools in 16 wt.% Si containing alloy, Barzani et al.²¹ found that F and Ra in turning of Sr added Al-11% Si-2% Cu alloy were less than the base alloy and antimony added alloy. The structural and mechanical properties of the newly developed ternary Al-9Si-0.1Sr and quaternary Al-9Si-0.1Sr-0.6Mg alloys have been revealed in detail in the literature.^14,22 However, effect of the Sr and Mg additions on the machinability properties of Al-9Si alloy have not been studied yet. Therefore, it was aimed to reveal the effects of Sr and Mg additions on the machinability characteristics of the Al-9Si alloy.

Material and method

Alloy production and chemical analysis

Al-9Si, Al-9Si-0.1Sr, and Al-9Si-0.1Sr-0.6Mg alloys were prepared by permanent mold casting. High purity (∼99.8 wt. %) Al, Si, Mg, and Al-15Sr master alloy were used in the production of the alloys. These alloying elements were melted in an induction melting furnace and solidified by pouring them into a conical shape SAE 8620 steel mold kept at room temperature from a casting temperature of approximately 750°C. Technical drawing of the mold used was given in the previous studies.^23–26 The compositions of the tested alloys have been confirmed inductively coupled with plasma – optical emission spectrometry (ICP – OES) technique.

Investigation of structural and mechanical properties

Samples taken from alloy ingots produced for microstructural examinations were polished with standard metallographic techniques. Polished alloy samples were examined without etching and micrographs showing the microstructures of the alloys were taken in NİKON made optical microscopy (OM). The phases forming the microstructure of the alloys were confirmed byX-ray diffraction (XRD) studies. XRD studies were carried out on flat samples by using PHILIPS PW-3710 brand X-ray diffractometer. Hardness measurements were carried out with Brinell method on the basis of previous works.^4,9 The hardness of each alloy was determined by averaging at least ten measurements. Tensile tests were carried out by using a universal test machine at a deformation rate of 10⁻³ s⁻¹. The technical drawing of the tensile test samples is given in Figure 1. Tensile tests were carried out at least six sample for each alloy. Yield and tensile strength and elongation to fracture values of the tested alloys were calculated by taking the average of the test results.

Figure 1.

Technical drawing of the tensile test samples.

Experimental devices and turning process conditions

The conically casted alloys were machined in the universal lathe as Ø58 × 200 mm before the experimental tests. Turning studies for cutting force and surface roughness were performed in a CNC Johnford TC-35 lathe using the Sandvik Coromant trade mark uncoated carbide inserts (Manufacturer code: DCGX11T304). New insert was used for each turning test. A photograph showing the experimental set up is given in Figure 2. Cutting speed, feed rate, and depth of cut were preferred as 550 m/min, 0.05 mm/rev, and 1.5 mm in the turning tests, respectively. These values were determined in line with the literature^20,27,28 and cutting insert manufacturer’s recommendation. Vibration signals in the course of turning were received by the Kistler 9257B dynamometer (Switzerland made) dynamometer and transferred to an amplifier. These signals were transferred from amplifier to a computer and transformed into charts by means of a Dynoware software to calculate the F (Figure 2).

Figure 2.

A photograph showing the experimental set up.

The F was calculated by the formula of $F = \sqrt{F_{f}^{2} + F_{t}^{2} + F_{c}^{2}}$ , where F_f is the feed force, F_t is the thrust force, and F_c is the main cutting force (Figure 3). The roughness of the machined surfaces was determined using a Mahr perthometer tracer-pointed device according to ISO 4287 standard. Three measurements were made on each alloy sample and the Ra of the machined surface was determined by averaging the obtained values. The average Ra value is calculated by the formula of $R_{a} = \frac{1}{L} \int_{0}^{L} | y (x) | dx$ , where Ra is the arithmetic mean of y coordinates, L is the measuring length, and y is the measured value.

Figure 3.

Sample graphic showing the cutting force signals.

Results and discussion

Structural and mechanical properties of the alloys

Chemical compositions of the tested alloys are given in Table 1. Al-9Si alloy comprised of α-Al, eutectic Al-Si, β, and primary Si phases, Figure 4. Formation of the α-Al and eutectic Al-Si phases in the Al-Si alloy is explained in detailed in the literature.^9,14,22β phase is an intermetallic phase formed by the reaction of iron, which is the impurity element in the produced alloys, with Al and Si.^9,14,22 It is known that primary Si particles in the hypoeutectic Al-Si alloys are formed due to non-equilibrium solidification conditions.⁹ The micrographs showing the microstructure of the Al-9Si-0.1Sr and Al-9Si-0.1Sr-0.6Mg alloy are given in Figures 5 and 6, respectively. The microstructure of the ternary Al-9Si-0.1Sr alloy consists of the α, eutectic Al-Si, primary Si, δ, and Al₄Sr phases (Figure 5). It was also observed that the volume ratio of α phase in Al-9Si-0.1Sr alloy was higher than that of binary Al-9Si. These influences of the Sr on the Al-Si alloys are explained in the literature.^{9,14,22,29,30} The addition of Mg to Al-9Si-0.1Sr alloy caused transformation of δ phase to π phase (Figure 6).⁹ It is known that intermetallic phases containing iron such as β, δ, and π in Al-Si alloys are formed and differ depending on the ratio of impurity elements and cooling conditions.^31–34 The results of XRD studies made for determining the phases are given in Figure 7. X-ray diffraction patterns of the alloys samples show that the peaks of the α (Al) phase are observed at the angles of 38°, 45°, 65°, 78°, 83°, the peaks of the Si phase are observed at the angles of 28°, 47°, 56°, 69°, 76°, 88°, the peak of the Al₄Sr phase is observed at angles of 45°. And the peaks of the β, δ, and π phases are observed at angles of 45°. These results are compatible with previous studies.^9,35 The absence of a peak of any phase containing Mg confirms that Mg fully dissolves in the microstructure of the Al-9Si-0.1Sr-0.6Mg alloy.

Table 1.

Chemical compositions of the tested alloys.

Alloy	Element (wt. %)
	Alloying element				Impurity elements
	Si	Sr	Mg	Al	Fe	P, V, Zn, Zr, Cu, Mn, Ni, Pb, Sn, Ti, Cr
Al-9Si	9.1	–	–	Balance	1.1	0.18
Al-9Si-0.1Sr	9.2	0.10	–	Balance	1.2	0.30
Al-9Si-0.1Sr-0.6Mg	9.2	0.12	0.63	Balance	1.2	0.28

Figure 4.

Metallographic structure of the Al-9Si alloy.

Figure 5.

Metallographic structure of the Al-9Si-0.1Sr.

Figure 6.

Metallographic structure of the Al-9Si-0.1Sr-0.6Mg.

Figure 7.

XRD pattern of the: (a) Al-9Si, (b) Al-9Si-0.1Sr, and (c) Al-9Si-0.1Sr-0.6Mg alloy.

The hardness, yield strength, tensile strength, and elongation to fracture values of the experimental alloys are given in Table 2. This table shows that the Sr addition increases the yield strength, tensile strength, and elongation to fracture of the Al-9Si alloy. This table also shows that certain rate (0.6 wt.%) Mg addition increases the hardness, yield, and tensile strength while decreasing the elongation to fracture of the Al-9Si-0.1Sr alloy. With the addition of 0.1 wt.% Sr, yield strength, tensile strength, and elongation to fracture of the Al-9Si alloy increased by approximately 7%, 6%, and 55%, respectively. In the case of adding 0.6 wt.% Mg to Al-9Si-0.1Sr alloy, hardness, yield strength, and tensile strength increased by approximately 24%, 39%, 12%, respectively, while elongation to fracture decreased by 4%. The effect of Sr and Mg additions on the material properties of Al-Si alloys is explained and discussed in detail in the literature based on the increase in the volume ratio of the α phase in addition to the effect of grain refinement, solid solution, and dispersion hardening mechanisms.⁹

Table 2.

The values of the hardness, yield strength, tensile strength, and elongation to fracture of the tested alloys.

Alloy	Hardness (HB)	Yield strength (MPa)	Tensile strength (MPa)	Elongation to fracture (%)
Al-9Si	52 ± 2	73 ± 2	154 ± 4	9 ± 3
Al-9Si-0.1Sr	51 ± 3	78 ± 3	163 ± 5	14 ± 4
Al-9Si-0.1Sr-0.6Mg	63 ± 2	108 ± 3	182 ± 6	5 ± 2

Machining tests were repeated five times for each alloy. The arithmetic mean values for the F and Ra obtained as a result of these machining tests were calculated. The arithmetic F and Ra values obtained in cutting tests are given in Table 3. It has been determined that the F is 128.101 N and the Ra is 0.617 µm in the machining of Al-9Si alloy in this table. The addition of 0.1 wt.% Sr to Al-9Si alloy increased the F by 2.632% and the average Ra by 32.739%.

Table 3.

The arithmetic average values of F and Ra of the tested alloys.

Alloy	F (N)	Ra (µm)
Al-9Si	128.101	0.617
Al-9Si-0.1Sr	131.382	0.819
Al-9Si-0.1Sr-0.6Mg	121.480	0.558

The addition of Sr facilitates the plastic deformation of the Al-based soft phase (α phase) by increasing the elongation to fracture of the alloy.²¹ This increases the chip contact surface area with the insert, causing continuous chip formation (Figure 8(b)). This increase in the contact area causes to adhere to the cutting tool rake face of the chip in the machining of ductile materials. Therefore, it causes the formation of BUE and BUL (Built up layer) on the rake face (Figure 9). This change in cutting tool geometry increases F and Ra.^16,36 Workpiece material in the machining of aluminum-based alloys adheres to the cutting tool in two different forms with the effect of temperature and pressure. These are BUE and BUL. BUE is the adhesion of the workpiece material to the cutting tool cutting edge while BUL is the adhesion of the workpiece material to the cutting tool rake face as a thin layer.^37–40 Yield strength of the material decreases and its ductility increases depending on the temperature increase during cutting at the cutting edge. This causes the formation of BUE and BUL in the cutting tool and increases the chip/cutting tool contact surface area. Volume of chip adhering to the cutting tool depending on the continuing cutting process increases. This increases the cutting force. In addition, it causes the separation of small particles from the cutting edge, the deterioration of the cutting tool geometry and the reduction of the machined surface quality.^38,41 It has been revealed in the literature studies that BUE is formed on the cutting edge with the effect of low hardness and high ductility properties in alloys containing high aluminum content.^42–46

Figure 8.

Chip formation in turning of alloys: (a) Al-9Si, (b) Al-9Si-0.1Sr, and (c) Al-9Si-0.1Sr-0.6Mg.

Figure 9.

BUE and BUL formation on cutting inserts: (a) Al-9Si, (b) Al-9Si-0.1Sr, and (c) Al-9Si-0.1Sr-0.6Mg.

It was determined that the addition of 0.6 wt. % Mg to Al-9Si-0.1Sr alloy reduced the F by 8.151% and the Ra by 46.774%. The addition of Mg causes solid solution strengthening and transformation of the δ phase to the π phase in the microstructure of the alloy. These result in a decrease in the elongation to fracture. As a result, the F and Ra decrease due to the decrease in the ductility of the alloy. As a result of the decrease in elongation to fracture, brittle chip formation was observed during cutting (Figure 8(c)). It is thought that as a result of solid solution strengthening and phase transformation, shorter chips are formed due to the fragile structure of the alloy. It is expected that solid solution strengthened matrix is a relatively hard and brittle and the intermetallic π phase are larger in size and do not tend to curl. Relatively hard and brittle matrix and intermetallic π phase facilitate the formation and propagation of cracks during cutting. Thus, a more fragile chip structure is formed. Brittle chip formation is also known from studies in the literature where it improves the material’s machinability. In addition, as a result of the reduction of the elongation to fracture of the alloy, it has been determined that the formation of BUE and BUL on the cutting tool rake face is less than other alloys (Figure 9(c)).^17,42,47,48 BUE is the debris of material in the area close to the cutting tool edge, while BUL is the adhesion of the material by extending on the rake face. Temperature increases in the first stage of the cutting process.^49,50 This temperature causes the melting of the α phase in the structure of the alloy flowing on the rake face of the cutting tool. Metal chips formed under these conditions will drag other elements in the structure of the alloy on the rake face. The layer consisting of the α phase and causing the formation of BUL is formed in the first stage of the cutting process. This situation causes extrusion on the rake face due to the first melting of the α phase and the impact of compression forces between the cutting tool and the chip. Thus, Si, Sr, and Mg elements with higher melting points drag on the rake face.³⁷ This situation is supported by SEM images (Figure 9) and EDS analysis as given in Figure 10. Accordingly, Al and Si in Figure 10(a), Al, Si, and Sr in Figure 10(b) and Al, Si, Sr, and Mg in Figure 10(c) were detected.

Figure 10.

EDS views for cutting tool rake face in Figure 9: (a) Al-9Si, (b) Al-9Si-0.1Sr, and (c) Al-9Si-0.1Sr-0.6Mg.

SEM images obtained from the machined surfaces are given in Figure 11. Relatively brittle fracture marks were more common in Al-9 Si and Al-9Si-0.1Sr-0.6Mg alloys while ductile fracture was observed to be more effective in Al-9Si-0.1Sr alloy. It was also observed that while the abrasion marks were more on the surfaces of the samples of the Al-9Si and Al-9Si-0.1Sr-0.6Mg alloys, the adhesion marks were more prominent on the surface of the Al-9Si-0.1Sr alloy sample. These results are thought to be related the elongation to fracture values or ductility of the tested alloys. It is well known that the alloys having lower elongation to fracture values exhibit brittle fracture while the alloys having higher the elongation to fracture value exhibit ductile fracture. It is expected that increased elongation to fracture and ductility also increases the adhesion mechanism. Therefore, it is thought that the Al-9Si and Al-9Si-0.1Sr-0.6Mg alloys having relatively lower elongation to fracture values or ductility compare to Al-9Si-0.1Sr alloy exhibit more brittle fracture and abrasion marks in the micrographs while Al-9Si-0.1Sr alloy exhibits more ductile fracture and adhesion marks.

Figure 11.

Surface texture in machining of alloys: (a) Al-9Si, (b) Al-9Si-0.1Sr, and (c) Al-9Si-0.1Sr-0.6Mg.

Conclusions

The machinability of Al-Si based alloys has some difficulties due to their material properties. Determination of F, Ra, tool wear, and chip morphology under predetermined cutting conditions is important for practical application. In this study, the impact of Sr and Mg on the machinability of Al-9Si alloy was investigated. Experimental inputs for machinability are cutting speed and feed rate parameters, while outputs are F, Ra, and tool wear. Experimental results were discussed on the basis of material properties. Accordingly, the conclusions for study can be given as follows;

– Microstructure of the Al-9Si alloy consisted ofα-Al, eutectic Al-Si, β, and primary Si phases. Sr addition (0.1 wt. %) to binary Al-9Si alloy caused the formation of the Al₄Sr phase and the transformation of the β phase into the δ phase. The addition of Mg (0.6 wt. %) to Al-9Si-0.1Sr caused the δ phase to transform into the π. phase.

– Certain rates of Sr and Mg additions increased the values of the yield strength and tensile strength of the Al-9Si alloy. While the elongation to fracture increased with the addition of 0.1 wt.% Sr to Al-9Si alloy, it decreased with the addition of 0.6 wt.% Mg to Al-9Si-0.1Sr alloy.

– The highest F and average Ra values were measured in turning of Al-9Si-0.1Sr, Al-9Si, and Al-9Si-0.1Sr-0.6Mg alloys, respectively. The best surface quality was observed in turning of Al-9Si-0.1Sr-0.6Mg alloy.

– Highest amount of BUE and BUL on the rake face were formed in Al-9Si-0.1Sr, Al-9Si, and Al-9Si-0.1Sr-0.6Mg alloys, respectively.

– Brittle chip formation was observed in turning of Al-9Si-0.1Sr-0.6Mg alloy, while semi-continuous and continuous chip formation was observed in Al-9Si and Al-9Si-0.1Sr alloys, respectively. It was also found that the brittle chip improves the machinability of the alloy.

– While adhered material and abrasion marks were formed on the machined surface of Al-9Si-0.1Sr alloy, it was determined that only abrasion marks were formed in other alloys.

– The F, Ra, BUE, and BUL formation were closely related to the elongation to fracture or ductility/brittleness properties of these alloys in the machining process.

Footnotes

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

ORCID iD

Şenol Bayraktar

References

Campbell

. Complete casting handbook: metal casting processes, metallurgy, techniques and design. Oxford: Butterworth-Heinemann. Elsevier Publishing, 2015.

Jorstad

Apelian

. Hypereutectic Al-Si alloys: practical casting considerations. Int J Metalcasting 2009; 3(3): 13–36.

European Standards. EN 1706-Aluminium and aluminium alloys-castings-chemical composition and mechanical properties. Slovenia: European Standards, 2020.

Hekimoglu

Hacıosmanoglu

. Microstructure and mechanical properties of Al-(2-30)Si Alloys. In: 3rd international conference on material science and technology in Cappadocia (IMSTEC’18), Nevsehir, Turkey, 17–19 September 2018.

Prabhudev

Auradi

Venkateswarlu

, et al. Influence of Cu addition on dry sliding wear behaviour of A356 alloy. Procedia Eng 2014; 97: 1361–1367.

, et al. Effects of the addition of Mg on the microstructure and mechanical properties of hypoeutectic Al–7%Si alloy. Int J Metalcasting 2017; 11: 823–830.

Kim

Jeong

. Mechanical and die soldering properties of Al–Si–Mg–Mn cast alloy. Mater Res Innov 2014; 18: 2666–2672.

Alemdağ

Beder

. Microstructural, mechanical and tribological properties of Al–7Si–(0–5)Zn alloys. Mater Des 2014; 63: 159–167.

Hekimoğlu

Çalış

Ayata

. Effect of strontium and magnesium additions on the microstructure and mechanical properties of Al–12Si alloys. Met Mater Int 2019; 25: 1488–1499.

10.

Huiyuan

Yanxiang

Xiang

, et al. Effects of boron on eutectic solidification in hypoeutectic Al–Si alloys. Scr Mater 2005; 53: 69–73.

11.

Nogita

Dahle

. Combining Sr and Na additions in hypoeutectic Al–Si foundry alloys. Mater Sci Eng A 2005; 399: 244–253.

12.

Liu

Chen

. The influence of the Al-Ti-B/Al-Sr modification on the microstructure and properties of the hypereutectic Al-Si alloy in automotive piston. Adv Mater Res 2013; 744: 339–344.

13.

Kumar

Sasikumar

. Effect of vanadium addition to Al-Si alloy on its mechanical, tribological and microstructure properties. Mater Today Proc 2017; 4: 307–313.

14.

Hekimoğlu

Çalış

Ayata

. Effect of strontium and strontium magnesium additions on structural and mechanical properties of the Al-9Si alloy. In: 1st international symposium on innovative approaches in scientific studies, Antalya, Turkey, 2018, pp.422–426.

15.

Farid

Sharif

Idris

. Surface integrity study of high-speed drilling of Al–Si alloy using HSS drill. Proc IMechE, Part B: J Engineering Manufacture 2011; 225: 1001–1007.

16.

Basavakumar

Mukunda

Chakraborty

. Influence of melt treatments and turning inserts on cutting force and surface integrity in turning of Al–12Si and Al–12Si–3Cu cast alloys. Surf Coat Technol 2007; 201: 4757–4766.

17.

Bayraktar

Afyon

. Machinability properties of Al–7Si, Al–7Si–4Zn and Al–7Si–4Zn–3Cu alloys. J Braz Soc Mech Sci Eng 2020; 42: 1–12.

18.

Zhang

Liu

, et al. Correlation between the microstructure and machinability in machining Al–(5–25) wt% Si alloys. Proc IMechE, Part B: J Engineering Manufacture 2020; 234: 1173–1184.

19.

Kamiya

Yakou

Sasaki

, et al. Effect of Si content on turning machinability of Al-Si binary alloy castings. Mater Trans 2008; 49: 587–592.

20.

Dos Santos

da Costa

Amorim

, et al. Characterization of DLC thin film and evaluation of machining forces using coated inserts in turning of Al–Si alloys. Surf Coat Technol 2007; 202: 1029–1033.

21.

Barzani

Farahany

Yusof

, et al. The influence of bismuth, antimony, and strontium on microstructure, thermal, and machinability of aluminum-Silicon Alloy. Mater Manuf Process 2013; 28: 1184–1190.

22.

Ayata

. Effect of addition of the boron, strontium and/or magnesium on the structural and mechanical properties of the Al-Si alloys. MSc Thesis, Recep Tayyip Erdogan University, Turkey, 2018.

23.

Savaşkan

Turhal

MŞ

. Relationships between cooling rate, copper content and mechanical properties of monotectoid based Zn–Al–Cu Alloys. Mater Charact 2003; 51: 259–270.

24.

Hekimoğlu

Savaşkan

. Structure and mechanical properties of Zn-(5–25) Al Alloys. Int J Mater Res 2014; 105: 1084–1089.

25.

Hekimoglu

Calis

. Effects of titanium addition on structural, mechanical, tribological, and corrosion properties of Al−25Zn−3Cu and Al−25Zn− 3Cu−3Si alloys. Trans Nonferrous Met Soc China 2020; 30: 303–317.

26.

Hekimoglu

Calis

. Effect of grain refinement with titanium on the microstructure, mechanical and corrosion properties of Al-25Zn alloy. J Fac Eng Arch Gazi Uni 2020; 35: 311–322.

27.

Marani

Songmene

Kouam

, et al. Experimental investigation on microstructure, mechanical properties and dust emission when milling Al-20Mg2Si-2Cu metal matrix composite with modifier elements. Int J Adv Manuf Technol 2018; 99: 789–802.

28.

Marani

Songmene

Zeinali

, et al. Neuro-fuzzy predictive model for surface roughness and cutting force of machined Al–20 Mg2Si–2Cu metal matrix composite using additives. Neural Comput Appl 2020; 32: 8115–8126.

29.

Liao

Sun

. Correlation between mechanical properties and amount of dendritic α-Al phase in as-cast near-eutectic Al–11.6% Si alloys modified with strontium. Mater Sci Eng A 2002; 335: 62–66.

30.

Wang

Mudassar

, et al. Effect of Sc and Sr on the eutectic Si morphology and tensile properties of Al-Si-Mg alloy. J Mater Eng Perform 2017; 26: 1605–1613.

31.

Hou

Cai

Cui

, et al. Microstructure evolution and phase transformation of traditional cast and spray-formed hypereutectic aluminium-silicon alloys induced by heat treatment. Int J Miner Metall Mater 2010; 17: 297–306.

32.

Wang

. Control of morphology Al-Fe-Si phase in Al-Si-Cu hypoeutectic alloy. PhD Thesis, Purdue University, USA, 2014.

33.

Timelli

Bonollo

. The influence of Cr content on the microstructure and mechanical properties of AlSi9Cu3(Fe) die-casting alloys. Mater Sci Eng A 2010; 528: 273–282.

34.

Nemri

Gueddouar

Benamar

MEA

, et al. Effect of Mg and Zn contents on the microstructures and mechanical properties of Al–Si–Cu–Mg alloys. Int J Metalcasting 2018; 12: 20–27.

35.

Hekimoglu

Hacıosmanoğlu

Baki

. Effect of zinc contents on the structural, mechanical and tribological properties of EN AC-48100 (Al-17Si-4Cu-Mg) alloy. J Fac Eng Arch Gazi Uni 2020; 35: 1799–1814.

36.

Marani Barzani

Zalnezhad

Sarhan

AAD

, et al. Fuzzy logic based model for predicting surface roughness of machined Al–Si–Cu–Fe die casting alloy using different additives-turning. Measurement 2015; 61: 150–161.

37.

Carrilero

Bienvenido

Sánchez

, et al. A SEM and EDS insight into the BUL and BUE differences in the turning processes of AA2024 Al–Cu alloy. Int J Mach Tools Manuf 2002; 42: 215–220.

38.

Gökkaya

Nalbant

. Investigating the effects of cutting speeds over the built-up layer and built-up edge formation with SEM. J Fac Eng Arch Gazi Uni 2007; 22: 481–488.

39.

Guntreddi

Ghosh

. High-speed machining of aluminium alloy using vegetable oil based small quantity lubrication. Proc IMechE, Part B: J Engineering Manufacture. Epub ahead of print 16 June 2020. DOI: 10.1177/0954405420929787.

40.

Saberi

Niknam

Hashemi

. On the impacts of cutting parameters on surface roughness, tool wear mode and size in slot milling of A356 metal matrix composites reinforced with silicon carbide elements. Proc IMechE, Part B: J Engineering Manufacture 2021; 235: 1655–1667.

41.

List

Nouari

Géhin

, et al. Wear behaviour of cemented carbide tools in dry machining of aluminium alloy. Wear 2005; 259: 1177–1189.

42.

Bayraktar Demir

. Processing of T6 heat-treated Al-12Si-0.6Mg alloy. Mater Manuf Process 2020; 35: 354–362.

43.

Acır

Turgut

Übeyli

, et al. A study on the cutting force in milling of boron carbide particle reinforced aluminium composite. Sci Eng Compos Mater 2009; 16: 187–196.

44.

Okay

Islak

Turgut

. Investigation of machinability properties of aluminium matrix hybrid composites. J Manuf Process 2021; 68: 85–94.

45.

Yücel

Yıldırım

ÇV

Sarıkaya

, et al. Influence of MoS₂ based nanofluid-MQL on tribological and machining characteristics in turning of AA 2024 T3 aluminum alloy. J Mater Res Technol 2021; 15: 1688–1704.

46.

Ekici

Motorcu

Uzun

. An investigation of the effects of cutting parameters and graphite reinforcement on quality characteristics during the drilling of Al/10B 4 C composites. Measurement 2017; 95: 395–404.

47.

Froehlich

Jacques

Strohaecker

, et al. The correlation of machinability and microstrutural characteristics of different extruded aluminum alloys. J Mater Eng Perform 2007; 16: 784–791.

48.

Bayraktar Hekimoğlu

. Effect of zinc content and cutting tool coating on the machinability of the Al-(5–35) Zn alloys. Met Mater Int 2020; 26: 477–490.

49.

Khanna

Suri

Shah

, et al. Cryogenic turning of in-house cast magnesium based mmcs: a comprehensive investigation. J Mater Res Technol 2020; 9: 7628–7643.

50.

Kharka

Jain

Gupta

. Influence of MQL and hobbing parameters on microgeometry deviations and flank roughness of spur gears manufactured by MQL assisted hobbing. J Mater Res Technol 2020; 9: 9646–9656.

Experimental research on machinability characteristics of Al-9Si alloy: Effect of Sr and Mg additives

Abstract

Keywords

Highlights

Introduction

Material and method

Alloy production and chemical analysis

Investigation of structural and mechanical properties

Experimental devices and turning process conditions

Results and discussion

Structural and mechanical properties of the alloys

Conclusions

Footnotes

Declaration of conflicting interests

Funding

ORCID iD

References