A Methodology for Predicting the Production Cost of Parts Fabricated Using Incremental Sheet Forming
Authors: Riofrio Mario Israel , Haapala Karl R. , Fan Zhaoyan 
Published: August 2024

Abstract
Amidst increasing governmental regulations and global initiatives to decarbonize manufacturing, there is a growing emphasis on environmentally sustainable, energy-efficient, and cost-effective production methods. Sheet-forming processes have made it possible to manufacture a variety of products we use and depend on in today’s globalized world, in the automotive, aerospace, medical, and food industries. Stamping or deep drawing are the preferred sheet-forming methods for mass-producing thin sheet parts due to its high production rate. However, the process involves high costs associated with the fabrication of specific dies for each part. Incremental sheet forming (ISF) has emerged as a promising technique and has gained widespread recognition as an alternative to traditional sheet forming. Researchers have studied ISF for the past decades, addressing and exploring alternatives to optimize the technique. Single-point incremental forming (SPIF) is one of the most popular ISF approaches because it can be accomplished using a CNC machine, a sheet clamp, and a small forming tool to make a wide variety of products of different shapes and materials. However, the technology’s cost-saving potential needs to be better understood, and predictive models must be improved to assess the process flows required to make parts using ISF. The cost prediction model presented in this work is intended to break down the cost dependencies of the ISF process to estimate a predetermined cost for each part before it is manufactured, considering material preparation, forming, and post-processing operations. A step forward in sheet forming research will be to provide a process-based cost model that can be flexible and adaptable to different types of machinery and tooling utilized. Cost calculations of a part made with ISF require knowledge of the systema as whole, such as forming process parameters, equipment characteristics, and forming geometry capabilities. The model relies on gathering process-based costs, including facilities, labor, equipment, materials, tools, consumables, and utilities, for all factors necessary to produce parts using ISF. The process-based cost model in this work involves an analytical bottom-up cost calculation methodology that is flexible and adaptable to various machine types. The ISF process is flexible, which means that the cycle time for different parts can vary by a considerable amount depending on the process parameters chosen (e.g., step down and feed rate) and the fixture and tools used. The aim of the present work is to lay the foundation for predicting the cost-effectiveness of products produced via the ISF process by considering the key processes involved. By gaining deeper insights into all costs involved in ISF and other innovative, environmentally friendly production methods, more sustainable manufacturing practices can be facilitated. These findings will contribute to global efforts to reduce carbon emissions, support responsible consumption and production, and benefit people, economy, and environment.