IORD Journal of Science & Technology E-ISSN: 2348-0831 Volume 2, Issue 3 (MAR-APR 2015) PP 110-116 IMPACT FACTOR 1.719 www.iord.in

Review of Automobile Wheel Rim Design, Materials and Its Considerations ShaileshPandit[1] and Dr. S Y Gajjal[2] [email protected][1] , [email protected],[2] PG Student, NBN SSOE, Pune, (M.S )[1] Prof.NBN SSOE, Pune(M.S.)[2]

ABSTRACT: Over the years a lot of work has done and is still continuing with great effort to save weight and cost of

applications. The current trend is to provide weight/cost effective products which meet the stringent requirements. The aim of this paper is to study Automobile Wheel Rim Design, Materials and its various Considerations for best design.Review is done for materials and design process used for wheel rim. Keyword: Wheel Rim, Wheel Disc Materials.

1.0. INTRODUCTION

1.1 Background Automotive wheels have evolved over the decades from early spoke designs ofwood and steel, carryovers from wagon and bicycle technology, to flat steel discs and finally to the stamped metal configurations and modern cast and forged aluminum alloysrims of today’s modern vehicles. Historically, successful designs arrived after years of experience and extensive field testing. Since the 1970's several innovative methods of testing well aided with experimental stress measurements have been initiated. In recent years, the procedures have been improved by a variety of experimental and analytical methods for structural analysis (strain gauge and finite element methods).Within the past 10 years, durability analysis (fatigue life predication) and reliability methods for dealing with the variations inherent in engineering structure have been applied to the automotive wheel. Fig 1.1Rim Tyre side profile Nomenclature

1.2 Stress analysis The performance of the wheel was evaluated as a function of the rim and disc plate thickness. The theoretical analysis of the stress and fatigue life was in good agreement with the result of a rotary corner fatigue test. In this study, radial loading was assumed to be the function of the cosine of the angle from the point of contact. The bending moment introduced as a result of the radial loading was directly affected by the radius as follows M=4* _ _ _ __ _ _ _ _ _ _ _ _(1.1)

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IORD Journal of Science & Technology E-ISSN: 2348-0831 Volume 2, Issue 3 (MAR-APR 2015) PP 110-116 IMPACT FACTOR 1.719 www.iord.in

With qo is the applied load due to weight is the angle from the point load, the maximum moment, M. 1.3 Rim Testing Wright focused solely on testing methods for rims, providing data on proper loading methods and strain gauge placement to yield accurate results. Static and dynamic testing methods were discussed during vehicle braking and cornering. Wright focused on most current quality control tests based on simple loading methods on accelerated test loading factors and test lives for passenger car and truck wheels. Motorcycle rims were also tested. Wright’s quality controlled tests methods addressed the wide divergence of opinions on accelerated load test factors and test lives for passenger cars and truck wheels, except for the curb swipe impact tests where an international standard exists. Wright's publication was based on Motor Industry Research Association (MIRA) standards. MIRA developed British and ISO standards for wheels in the United Kingdom. Several good photographs of testing equipment can be seen in this publication.

1.4 Rim design Krause described a method of wheel assembly testing by stress analysis as an alternative to fatigue testing of wheel components, for evaluating the serviceability of wheel components, as well as, optimized wheel design. The results of stress analysis were compared with material fatigue properties. The loads applied in this stress analysis and in the material fatigue testing were derived from stress cumulative occurring in the actual vehicle service. This stress analysis was of the experimental type and was performed on a specially built slow rolling test bench. Distribution of the force was a function of the cosine angle about the applied load, and the loading equation can be expressed as P= This relationship is similar in many papers cited. The load fell to zero at 90 degrees. Stresses at the interface of the disc and the rim were the critical area of concern. At the point of contact with the ground, the angle of zero, the stress level at the interface of the disk and rim is in compression. At about 30 degrees rotation the stress level dropped to zero and continued in tension and peaking at the 90 degrees angle. 1.5 Objectives and Scope

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 The Objective of this research is to investigate the procedure of Rim manufacturing and assembly of Rim and Disc and finding the options for Optimization.  Also other objective is to investigate the effects of tyre air pressure in conjunction with the radial load on the Stress and Displacement in tyre rims, through Experimental Stress Analysis and Finite Element Analysis.  The scope of the loading analysis will be limited to the load due to the weight of the bike and inflation pressure only. 2.0. WHEEL MATERIALS 2.1] Introduction The development of wheel is traced from a material viewpoint beginning with wood, the first documented wheel material and ending with new materials under development such as composites and titanium. While it is impossible to imagine what civilization would like without a wheel, many early civilizations has numerous other tools but did not posses wheels. Undocumented legend has it that Chinese philosopher was inspired while watching a flower rolled by wind over the grass. In the period from 1900 to 1935 there were many different types of wheel materials and methods of construction in use. These include wood spoke, cast and forged steel, disc steel, cast Aluminum and wire wheels. Of all the material used in early 1900’s only one is not still in use today- wood (fig.2.1).

Fig.2.1 (Material – Time relationship) The predominant wheel material is now steel but the shape, size and method of manufacturing have drastically changed. By 1935 the passenger car wheel diameter has been reduced from 36” to 16” and rim width

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IORD Journal of Science & Technology E-ISSN: 2348-0831 Volume 2, Issue 3 (MAR-APR 2015) PP 110-116 IMPACT FACTOR 1.719 www.iord.in is increased from 3” to 6” with shrunk in rim diameter from 36” to 44” diameter to 20” to 24” diameter. 2.2] Steel Rimmed steel in SAE grade 1012 and 1015 were used for the disc because on hot rolled sheet that was very low in alloy content. SAE Grade

Typical Chemistry (%)

Rim C1008/1010

C Mn P 0.10 0.35 0.04

S 0.05

Disc C1012/1015

0.13 0.35

0.05

0.04

Minimum Typical Properties (KPa) TYS TS %E 206700 310050 30 206700 30

310050

Table 2.1 Typical Disc wheel materials 2.2.1] Stamped steel wheels Stamped steel wheels are most frequently used automotive wheels. The advantage of stamped wheels includes low cost and easy manufacturing. Disadvantage of steel wheels includes weight and styling difficulties that are often require the use of wheel covers and special lug nuts. The physical appearance of stamped wheels defines a symmetrical, thin walled, locally strongly curved structure.

Fig 2.2.Relation between tensile strength &elongation 2.2.2] Styled steel By 1960’s steel began to serve styling function in addition to supporting the vehicle. The disc or centre of the wheel was formed I many decorative designs that required upto nine die operation to manufacture. These discs are normally produced from hot rolled SAE 1012/1015 steel to provide the formability necessary for the complex shapes. 2.3] Polycast An extremely versatile styled manufacturing process consists of permanently molding self skinning polyurethane foam to the face of a steel wheel. The surface of the foam is then painted with urethane paints to accent the molded in styling features. Base coat/clear coat finish system is applied for a deep brilliant, high gloss appearance. The polycast can be molded all the way to the rim flange so no trim is required or a small trim ring can be used to cover the balance weights. 2.4] Aluminum The most popular casting alloy is A356-T6 whose mechanical properties are listed in table 3.4. Forged truck wheels are usually produced in three or more die operation that involves forging, extruding and hot forming. Forged truck wheels were first introduced in 1948 and in 1973 forged passenger car wheels were introduced. From 1947

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IORD Journal of Science & Technology E-ISSN: 2348-0831 Volume 2, Issue 3 (MAR-APR 2015) PP 110-116 IMPACT FACTOR 1.719 www.iord.in to 1966, 2024-T6 aluminum was used but that was replaced with 6061-T6 for improved corrosion resistance and formability at some sacrifice in mechanical properties (Table 2.4).

Tensile strength (kpa) Tensile yield strength (kpa) Elongation Fatigue strength

2024-T4

6061-T6

5454-0

399620

310050

227370

A356T6 227370

261820

220480

103350

137800

3.0. MATHEMATICAL MODELING OF RIM 3.1] Introduction In order to evaluate the effect of vehicle weight on tyre – rim interface and rim performance methodologies for modeling the effect of the vehicle weight as it is transferred to the rim. Methods explained are referenced in the published literature and analogies taken from thick ring theory in stress analysis in the development of loadings on links and eye-bars. 3.2] Eye-bar analogy

8 20

35 14

22 14

8.5 11

Table 2.4Mechanical properties of Forged, Sheet and Cast Aluminum alloys for wheels 2.5] Magnesium They typically provide lighter weight and improved performance as well as styling. Corrosion resistance has been an issue with magnesium wheels and they cannot provide the bright machined appearance that aluminum does. Comparison of material properties shows that magnesium is about two third the density of aluminum but has a lower modulus and lower mechanical properties.

Comparing a round rod in an eye bar under an equilibrium of forces as shown in Figure 3.1 In this figure, r, is the radius of the hole, W is the load imparted,  is the angle and is the maximum point load. The horizontal components of q are in balance with each other.The vertical forces can be related to the external load, W which is expressed as follows: _ _ _ _ _ _ _ _ _ _ _ _ _ (3.1) By defining q= and substituting into above equation, _ _ _ _ _ _ _ _ _ _ _ _ (3.2) Integrating yields,

2.6] Composite Fiber reinforced composites using thermoset resins are not new to the list of wheel materials. As early as 1966’s wheel programs were initiated by number of companies worldwide. Michelin produced wheels that were sold as a limited option on the 1971 citroen. More recently work has been done by Firestone, Ford, General motors, Motors, Motor wheel, Owens cornering, Rhodea Incorporated, Volkswagen and others. In 1985 Marsh’s racing tyres marketed a thermoplastic wheel for off road racing applications.

W = 2 * r * * [ _ ___ _ _ _ _ (3.3)

Summary

Evaluating,

Since from early 1900’s wood spoke wheel rim to nowadays composite wheel rim materials and high strength steel for rim use are covered. According to the requirement of automobile field and its reliability we are having steel,polycast, Aluminum, Magnesium, composite wheel rim materials available in the market.

W = 2 * r * *{[(π)/2 + sin2*(π/2)/4] – 0} __ (3.4)

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Fig. 3.1Eye-bar loading

= 2* W / π * r _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ (3.5) is in unit load N/mm and r is the radius of the bead seat. Normally this radius is assumed to be nearly equal to the

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IORD Journal of Science & Technology E-ISSN: 2348-0831 Volume 2, Issue 3 (MAR-APR 2015) PP 110-116 IMPACT FACTOR 1.719 www.iord.in pin radius. Dividing by qmax by its width of the eye-bar cross section gives the compressive stress based on the above model.

W = * _ _ __ _ _ __ (3.9)

Employing the Eye – bar analogy to Honda Activa wheel rim, The radial load acting on rim = W = 200kg. Bead seat radius = 4.5 mm. From equation (4.5) = (2*200*9.81) / (π*4.5) = 277.566 N/mm

W = 4 * b * * * ( / π )_ _ _ _ _ _ _ _ _ _ (3.10)

The compressive stress induced in rim = / b

On Integrating,

On solving for , = (W *π ) / ( 4 * b * * )_ _ _ _ _ _ _ _ _ _ (3.11) Where, is the radius of the bead seat and b is the width of the bead seat.

Where, b = bead seat width = 14 mm = 277.566 / 14 = 19.826 N / 3.3] Analysis under Radial load The total weight of a car is balanced with a vertical reaction force from the road through the tyre. This load constantly compresses the wheel radially. While the car is running, the radial load becomes a cyclic load with the rotation of the wheel. Hence, the evaluation of wheel fatigue strength under radial load is an important performance characteristic for structural integrity. According to the SAE specification, a wheel should maintain structural integrity without any cracks or plastic deformation for more than 4 x rotations under a radial load. The radial load, Q, is expressed by: Q = * W _ _ _ _ _ _ _ _ _ _ _ _ (3.6) Where is acceleration test factor () and W means maximum tyre load. In an actual wheel, since a radial load is applied to the wheel on the bead seats with the tyre, the distributed pressure is loaded directly on the bead seats of the model. The pressure is assumed to have a cosine function distribution mode within a central angle of 40 degree in a circumferential direction as shown in Figure 3.2. By using the cosine function accordingly, the distributed pressure, Wr, is given by the following equation: = * cos (π/2 * /)_ _ _ _ _ _ _ _ _ _ _ _ _ (3.7) The total radial load W is calculated by using equation 3.7 * _ _ _ _ _ _ _ _ _ _ _ _____ (3.8) Substituting eqn.4.8 in eqn.4.7 yields

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Fig.3.2Radial loading schematic The above derivation assumes that loads are vertical in nature. However true pressure loading is always applied normal to the surface of the bead seat, so a horizontal and vertical vector components need to be accounted for. Thus, we will revise equation (3.7) Let, F = p (). N _ _ _ _ _ _ _ _ _______________(3.12) using equation 3.7, and modified to account for horizontal components yields W = * (- sin + cos) _ _ _ _(3.13) Now eq. 3.9 is modified to yield the integral = [W * ( - 4)] / [ 4 * b * * ] _ _ _ (3.14) gives W, in rim with bead seat radius and b bead seat width,  the loading angle, the angle at maximum load. Under radial load of 200kg in Activa wheel rim, the stress induced is given by equation (3.11) = (W *π) / ( 4 * b * * ) = ( 200 * 9.81 * π) / ( 4*14*4.5*0.698 ) = 35.024 N / 3.4] Contact patch method

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IORD Journal of Science & Technology E-ISSN: 2348-0831 Volume 2, Issue 3 (MAR-APR 2015) PP 110-116 IMPACT FACTOR 1.719 www.iord.in In order to establish the response the interface of the two components can be established using contact elements.

2. Rim Structure drawing Fig 3.3.Contact path schematic Preliminary literature revealed that actual load on the tyre – rim takes the form of cosine function having a central angle of about measure from either side Wr of the point of contact with the ground (Fig. 3.3). While others assumed this angle is developed from the contact patch geometry of the tyre, considering that the tyre is loaded there is flat spot at the point of contact with the ground, this is called patch and the length of this patch is then converted to an equivalent angle swept by the bead seat area in contact with tyre rim. Summary Mathematical modeling of wheel rim covers Eye – Bar analogy, analysis under radial load and contact patch method. These are mathematical analogies for wheel rim. It provides good solution to evaluate the performance of wheel rim under loading conditions described. 1.

FIG. 3D Model of Wheel Rim:- (Exploded View of Rim and Disc)

Disk Drawing:

FIG. Assembled View of Rim and Disc

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IORD Journal of Science & Technology E-ISSN: 2348-0831 Volume 2, Issue 3 (MAR-APR 2015) PP 110-116 IMPACT FACTOR 1.719 www.iord.in Industrial Engineering (IJMIE), ISSN No. 2231 – 6477, Vol-2, Issue-1, 2012 3] “Design and Weight Optimization of Aluminum Alloy Wheel” by Sourav Das, (CAE Analyst) Altair Engineering India Pvt Ltd, Bangalore at International Journal of Scientific and Research Publications, Volume 4, Issue 6, June 2014 ISSN 2250-3153

4.0. CONCLUSION&FUTURE SCOPE 4.1 Conclusion

4] “Computer Aided Design and Simulation of Radial Fatigue Test of Automobile Rim Using ANSYS” by Emmanuel M. Adigio and Ebughni O. Nangi at IOSR Journal of Mechanical and Civil Engineering (IOSRJMCE) e-ISSN: 2278-1684,p-ISSN: 2320-334X, Volume 11, Issue 1 Ver. IV (Feb. 2014), PP 68-73

Following the described objective, the state of stress and mechanical response of aluminum automobile rims has been established, and the effects of inflation pressure are now well understood, in addition to the imposed radial load. The extensive literature search revealed the need to further investigate the effect of inflation pressure on the state of stress in the rim, and to provide a finite element analysis using the more accurate brick element rather than the shell or plate element as used in past publications.

5] “Topology Optimization of Aluminum Alloy Wheel” by Ch. P. V. Ravi Kumar1, Prof. R. SatyaMeher at International Journal of Modern Engineering Research (IJMER) Vol. 3, Issue. 3, May-June. 2013 pp-15481553 ISSN: 2249-6645

4.2 Future Work

7]“Fatigue Analysis of an Automobile Wheel Rim” Case study

6]“Finite Element Analysis of the Classic Bicycle Wheel” by Andrew D. Hartz at Rose-Hulman Institute of Technology ME522 Finite Element Analysis conference July 18, 2002.

1. FEA analysis of the Rim for said loading conditions.

2. Experimentation of the Wheel Rim for validating the FEA results. 3. Comparison and conclusion of the same. 4. Recommendation of best possible i.e. Optimized solution. REFERENCES 1]“A Review on Modeling and Analysis of Car Wheel Rim using CATIA & ANSYS” by T. Siva Prasad,T. Krishnaiah, J. Md. Iliyas, M.Jayapal Reddy at International Journal of Innovative Science and Modern Engineering (IJISME) ISSN: 2319-6386, Volume-2, Issue-6, May 2014 2]“Fatigue Analysis of Aluminum Alloy Wheel Under Radial Load” by N. Satyanarayana&Ch.Sambaiah at International Journal of Mechanical and

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