CHAPTER 2LITERATURE REVIEWSugar palm tree
The sugar palm tree (Arenga pinnata) is a member of the Palmae family and naturally a forest species (Siregar et al., 2005). It belongs to the sub-family of Arecoideae and tribe of Caryoteae (Sanyang et al., 2015). This plant is normally found in hot, humid parts of the Asian tropics, and it has the widest range of uses, which makes it a multipurpose palm species (Mogea et al. 1991. The sugar palm tree is believed to be a native to Southeast Asia, and can also be found in rainforest and dry forest (Orwa et al., 2009). In Indonesia, there are about 150 vernacular names for this multipurpose palm, including but not limited to “kelapa”, “merah”, “semut”, “gomuti”, “kaong”, and “aren” (Heyne 1950); in Malaysia it is called “enau” or “kabung” (Ishaket al. 2013). The sugar palm tree grows best in warm, tropical conditions with good sunlight and water supplies all year round on fertile soil. In Malaysia, sugar palm trees are found along the rivers in rural areas; its plantation growth covers approximately 892 hectares (Sahari et al. 2012b).
The sugar palm tree can grow from the lowland up to the altitude of about 1400 m (Mogea et al. 1991). Its trunk is solitary, straight, and usually 15 to 20 m in height and upwards to 65 cm in diameter (Sanyang et al. 2016b). It has large leaves up to 6 m long. The trunk is covered with black fibrous hair, commonly known as Ijuk or Injuk. The fibres found along its height have different chemical compositions and therefore vary in properties (Ishak et al. 2012). The sugar palm tree starts to flower between the age of 10 to 12 years, but early flowering can occur as early as 5 to 6 years. The tree dies after a lifetime of 12 to 20 years depending on the harvest environment (Mogea et al. 1991; Suwartapradja 2003). Figure 1 shows pictures of sugar palm trees (Wanderer 2010).
Figure 1: Sugar palm trees (Arenga pinnata)
The anti-roll bar (ARB) is one element in a car’s suspension that can reduce vibration and keep the tyres are in contact with road. The anti-roll bar, also recognize as the stabilizer bar, is a component that is installed in a vehicle to counteract the force that provoke swaying of the vehicle during occurs during cornering or due to road irregularities. Three aspects that a vehicle suspension system has to provide compromise solutions such as ride comfort, handling, and road holding. Ride comfort requires insulating the vehicle and its occupants from vibrations and shocks caused by the road surface. Handling requires providing safety in maneuvers and in ease in steering. The tires must be kept in contact with the road surface in order to ensure directional control and stability with adequate traction and braking capabilities for good road holding (Ünlüsoy, 2000). As has been a suspension component, ARB is used to improve the vehicle performance with respect to these three aspects (Kemal, 2003). A typical ARB is shown in Fig 2.
Figure 2: Typical anti roll bar (www.motorera.com, 2009)
Materials for anti-roll bar (ARB)
Spring steel is one of the materials that are commonly used as a core material in the design of ARBs. Topaz, engineer ; Kuralay (2011) manufactured 50CrV4 (51CrV4) spring steel that is suitable for the design of highly stresses springs. ARBs are usually manufactured from SAE Class 550 and Class 700 Steels. The steels included in this class have SAE codes from G5160 to G6150 and G1065 to G1090, respectively (Hubert ; Kumar et al., 2005). On the other hand, Schulz and Braun (2012) invented an ARB using a rope as a core from wound or braided fibres bonded with resin. In addition, Doody’s (2013) research states hybrid carbon fibre could be used as a suitable material for ARBs. With the research nowadays, materials substitution in the designing of ARBs, could be a great potential for the fibre reinforced composite as a suitable material to produce ARBs.
Natural fibre-based composites can be found in various application including in the automotive industry. For example, hemp, sisal, jute kenaf and coir have been applied in the design of automotive component (Furtada et al., 2014). Therefore, when using natural fibre in ARB design, cost and weight can be reduce (Dunne, Desai, Sadiku & Jayaramudu, 2016, Pickering, 2008)
Since sugar palm contains the highest percentage of lignin content compared to the other fibres. This would imply that sugar palm has a great potential for engineering application, after extensive studies. As it has the highest score with regard to lignin content, this shows great performance of the domestic natural fibre in terms of strength, rigidity and elasticity (Mastura et al., 2017).