Analisa Kekuatan Material Aisi 1018 dan 1020 pada Sasis Semi Ladder Frame Menggunakan Metode Finite Element Analysis

This study analyzes the structural strength of a semi-ladder frame chassis by comparing AISI 1018 and AISI 1020 steel using Finite Element Analysis (FEA) in SolidWorks under incremental loading from 1,000 to 5,000 kgf. At the peak
operational load (2,000 kgf), both materials exhibited an identical maximum deflection of 0.8475 mm on the Side Body Support Rail, which remains well below the allowable limit of 2.655 mm. The highest Von Mises stresses were concentrated in the rear kick-up curvature due to the notch effect, reaching 149.0 MPa for AISI 1018 and 148.8 MPa for AISI 1020. The chassis remained within the safe operating
range under loads of 1,000–2,000 kgf (Factor of Safety / FoS ≥ 1.5), entered a critical state at 3,000 kgf, and underwent plastic deformation starting at 4,000 kgf (FoS < 1.0). AISI 1018 steel was selected as the optimal material because its higher intrinsic yield strength (370.0 MPa vs. 351.6 MPa) yielded a superior minimum FoS (2.484 vs. 2.362). This additional 5.17% safety margin is crucial for ensuring chassis reliability against dynamic shock loads on the road.