Wire Arc Additive Manufacturing (WAAM) offers 2.5x lower environmental impact than CNC milling for marine propellers.

Why It Matters

This research provides critical data for designers and manufacturers to select the most sustainable and cost-effective production methods. Understanding the trade-offs between different manufacturing processes, especially for complex components like marine propellers, is essential for reducing environmental footprint and optimizing production economics.

Key Finding

For marine propellers, Wire Arc Additive Manufacturing (WAAM) is significantly more environmentally friendly and cost-effective than traditional CNC milling and Selective Laser Melting (SLM), primarily due to its efficient use of materials and energy.

Key Findings

• WAAM demonstrates approximately 2.5 times lower environmental impact than CNC milling and 3.4 times lower than SLM.
• WAAM is also the most cost-efficient approach.
• WAAM's efficiency stems from superior material and energy utilization.
• Optimal parameters for WAAM include a post-processing material allowance under 4 mm and finish machining velocities below 96 m/min.

Research Evidence

Aim: To compare the environmental impact and production costs of manufacturing a marine propeller using pure subtractive CNC milling, Wire Arc Additive Manufacturing (WAAM), and Selective Laser Melting (SLM).

Method: Comparative Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) analysis.

Procedure: Models were developed to quantify environmental impacts (LCA) and production costs (LCC) for each manufacturing approach. Input data was collected for raw materials, energy consumption, and post-processing. Key variables like material allowance and machining velocity were analyzed, and Monte Carlo simulations were used for uncertainty assessment.

Context: Manufacturing of marine propellers.

Design Principle

Prioritize manufacturing processes that minimize material waste and energy consumption throughout the product lifecycle.

How to Apply

When evaluating manufacturing options for metal components, conduct a comparative LCA and LCC to identify the most sustainable and economically viable approach, paying close attention to material efficiency and energy consumption.

Limitations

The analysis is specific to a marine propeller and may vary for different component geometries and material requirements. Uncertainty in input data can affect the precision of the results.

Student Guide (IB Design Technology)

Simple Explanation: Making big metal parts like boat propellers can be done in different ways. This study found that a newer method called WAAM uses less energy and materials, making it much better for the environment and cheaper than older methods like CNC milling.

Why This Matters: This research helps you understand that the way you choose to make your design has a big impact on the environment and how much it costs. Choosing a more sustainable manufacturing process can make your design project more responsible.

Critical Thinking: How might the scale of production (e.g., mass production vs. bespoke manufacturing) influence the comparative advantages of WAAM, CNC milling, and SLM?

IA-Ready Paragraph: The selection of manufacturing processes significantly impacts a product's environmental footprint and economic viability. Research by Kokare, Oliveira, and Godina (2023) demonstrated that for marine propellers, Wire Arc Additive Manufacturing (WAAM) offered a substantially lower environmental impact (2.5x less than CNC milling) and cost-effectiveness compared to traditional subtractive methods and Selective Laser Melting (SLM), primarily due to superior material and energy efficiencies. This highlights the importance of considering lifecycle assessments when choosing production methods.

Project Tips

• When choosing a manufacturing process for your design, think about its environmental impact and cost from start to finish.
• Research different manufacturing techniques and their associated resource usage and waste generation.

How to Use in IA

• Reference this study when discussing the environmental and economic implications of your chosen manufacturing method, especially if comparing different options.
• Use the findings to justify the selection of a particular manufacturing process based on sustainability metrics.

Examiner Tips

• Demonstrate an understanding of the full lifecycle impact of manufacturing choices, not just the initial design.
• Justify your manufacturing process selection with quantitative data on environmental and economic factors.

Independent Variable: ["Manufacturing approach (CNC milling, WAAM, SLM)","Post-processing material allowance","Finish machining velocity"]

Dependent Variable: ["Environmental impact (e.g., CO2 emissions, energy consumption)","Production cost"]

Controlled Variables: ["Component geometry (marine propeller)","Material type"]

Strengths

• Comprehensive comparative analysis using established methodologies (LCA, LCC).
• Inclusion of uncertainty analysis (Monte Carlo) to assess the robustness of findings.

Critical Questions

• To what extent can the findings regarding WAAM's efficiency be generalized to other complex metal components?
• What are the trade-offs in terms of design freedom and achievable surface finish between WAAM and CNC milling for this application?

Extended Essay Application

• Investigate the LCA and LCC of different manufacturing techniques for a chosen design project, comparing at least two methods.
• Explore how design choices (e.g., material selection, complexity) influence the environmental and economic outcomes of different production processes.

Source

A LCA and LCC analysis of pure subtractive manufacturing, wire arc additive manufacturing, and selective laser melting approaches · Journal of Manufacturing Processes · 2023 · 10.1016/j.jmapro.2023.05.102