**6.1 MAM challenges, issues, and approached solutions**

Despite the ability of the MAM method in reducing the complexity of parts to simple 2D slices and machining super hard alloys, the MAM method is still suffering from several issues and challenges which are interrupting its progress. In this sub-section, these challenges and issues will be discussed, and the solution approached by the author will be presented.

## *6.1.1 Lack of knowledge of design for additive manufacturing*

Understanding how the materials work in MAM and how the metals are printed layer by layer to print three dimensional models are big concerns in the design for additive manufacturing. Lack of understanding the differences between plastic 3D printing and metal 3D printing can lead to parts with low quality, high defects, and high probability of failure. Skills gap in MAM method is considered an important issue. The knowledge of transferring several subtractive manufacturing processes to one metal additive manufacturing process is a big step. Selecting the appropriate metals (powder or wire) to print the parts and the appropriate process requires a significant amount of knowledge. Also, understanding the orientation of parts and adjusting the support materials in right place by using the printer software before printing is important to obtain desirable quality and characteristics. Similarly, printing high quality parts with complex geometry is also a big challenge with the MAM method, especially when printing aerospace or firearm parts. Therefore, lack of education issue can cause companies to lag or fail in performing successful MAM.

#### *6.1.1.1 Proposed solution*

Well-trained workers or engineers and skilled workforce are necessary to diminish this problem. Building and finding capable workforce is not easy and requires

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*An Investigation of the Metal Additive Manufacturing Issues and Perspective for Solutions…*

effort and time. It also requires a significant work to shift into new, important method such as MAM. To enable the transition between general AM and MAM, more focus is needed on hiring well educated people in this field. Transition process from conventional manufacturing to MAM does need to shrink the workforce. Small workforce is required in MAM. For example, traditional manufacturing system needs 12 skilled workers and 7 engineers to run and manage the system, but MAM system might only require two well-trained, knowledgeable engineers to perform the same work. Building new techniques such as generative design and generative orientation is also beneficial to perform this transition. Finally, in the opinion of author, transformation to MAM should be executed by an educated and a knowledgeable workforce. This could be obtained by creating a custom plan for

The MAM method is still facing a lot of variation in parts. The problem that companies encounter is to create two similar parts, then make these parts repeatedly. America Makes Company is still suffering from this problem in MAM and only 30% from the produced parts meet the specifications of the company. In addition to this problem, the MAM method is also suffering from mass production process [2].

The repeatability inside the MAM system can be acquired by developing the standardization of quality. A standardization should be set for the MAM process. This standardization should be developed after a massive study on every MAM process and from this study several factors, such as MAM process type, printing time, environment, used materials, part size, production rate, complexity of the part, functionality and process setting need to be discussed and assigned to standardize the process. All these factors need to be organized and assigned inside specific range

which can provide the quality that is required to obtain the repeatability.

complex parts can be produced successfully on a SLM or DMLS system.

Making MAM process selection map is a good solution for eliminating this obstacle. This map will contain inputs and outputs. The inputs will have process parameters, such as part size, part geometry, material used, quality and mechanical properties required, and design parameters. These inputs will be analyzed and addressed, then they will be matched with each MAM process capability. Finally, the outputs will be extracted from all of that and the priority of using the MAM processes will be ordered according to their fitness for printing the required parts.

Every MAM process has different strength and ability to produce specific metallic part, whether the process is Powder Bed Fusion (PBF) or Direct Energy Deposition (DED) process. Using an appropriate process in MAM method will lead to produce defect-free parts. For example, using EBM process that has a high-power source will allow to produce a thicker layer, and will lead to high production rate. However, using the EBM process to produce tiny and complex part with lot of features will be a challenge because the residual powder in each layer will be semi sintered with thicker layer that will create part with undesired quality. Therefore,

*DOI: http://dx.doi.org/10.5772/intechopen.93630*

*6.1.2 Repeatability*

*6.1.2.1 Proposed solution*

*6.1.3.1 Proposed solution*

*6.1.3 Selecting an appropriate MAM process*

every company about the transmission and the risk of it.

*An Investigation of the Metal Additive Manufacturing Issues and Perspective for Solutions… DOI: http://dx.doi.org/10.5772/intechopen.93630*

effort and time. It also requires a significant work to shift into new, important method such as MAM. To enable the transition between general AM and MAM, more focus is needed on hiring well educated people in this field. Transition process from conventional manufacturing to MAM does need to shrink the workforce. Small workforce is required in MAM. For example, traditional manufacturing system needs 12 skilled workers and 7 engineers to run and manage the system, but MAM system might only require two well-trained, knowledgeable engineers to perform the same work. Building new techniques such as generative design and generative orientation is also beneficial to perform this transition. Finally, in the opinion of author, transformation to MAM should be executed by an educated and a knowledgeable workforce. This could be obtained by creating a custom plan for every company about the transmission and the risk of it.
