Comparing AM Materials

Mechanical Properties of AM Polymers

The charts below compare the tensile mechanics of polymer components made by FFF/FDM, SLA, SLS, and Material Jetting, as well as polymers processed by injection molding (IM) which can be taken as a benchmark for many AM thermoplastics. The data includes fiber-reinforced polymers. The data is color-coded by process, placing your cursor over each point shows the related details including the material, manufacturer, and in some cases the test or printing orientation. For simplicity of viewing, single point values are reported, without indication of statistical variation.

From the charts below, you may note:

    • Collectively, AM polymers span a wide range of tensile mechanical behavior, and both thermoplastics and photopolymers (thermosets) can exhibit significant elongation (strain) before failure, but this comes with a tradeoff in strength.
    • Fiber-reinforced polymers have the highest modulus and tensile strength of all noted materials; in the comparison here, the strongest commercially available AM polymers are (excluding continuous fiber reinforcement*) are short carbon fiber-reinforced FFF and SLS materials.
    • The strength and elongation of AM polymers is close to, yet does not quite meet the standard values for the same polymers processed by IM. This is because process-specific defects, such as surface roughness (in all processes) and weak interlayer adhesion (in FFF/FDM) can lead to premature failure.
    • Among thermoplastics, high-performance materials such as ULTEM and PPSF have the highest reported modulus and strength.
    • The anisotropy of FFF/FDM parts is noted, and depends on material and printing parameters.

    Source: MIT

    Source: MIT

    Source: MIT

    Source: MIT

    Source: MIT

    In many cases, commercial datasheets for the materials (and many others) represented in the charts can be easily found through an online search with the manufacturer and/or material name. These data sheets contain many other properties of interest, which were not tabulated here.

    *The Markforged composite printing technology–which is analogous to FFF but enables continuous fibers to be printed within solid thermoplastic parts–achieves tensile moduli of ~20-50 GPa and tensile strength exceeding 0.5 GPa, depending on the fiber reinforcement material.

    For further reading on the mechanical properties of AM polymers, you may consult:

    Mechanical Properties of AM Metals

    In the charts that follow, we provide exemplary data on the elastic (Young’s Modulus), plastic (yield and tensile strength), and fracture (maximum elongation) properties of metals commonly used in AM. The selected alloys: SS316L, Ti6Al4V, SS17-4PH, and Al10SiMg, are a small sample of the materials under investigation using metal AM. This is a small set of the many alloy compositions that can be explored using AM, and the complex space that connects alloy composition and processing parameters to these final properties. Even steels have a diverse library of composition, microstructure, and mechanical characteristics. These four alloy systems are chosen for the data presentation because data on each is available from reliable sources, and the AM properties can be compared to standard values for conventional processes such as casting, forging, and metal injection molding. The goal is for you to explore this data on your own, and make observations as to the relationships between the process, treatment conditions (e.g., annealing or sintering), and properties.

    Source: MIT

    Source: MIT

    Source: MIT

    Source: MIT

    Source: MIT

    Source: MIT

    Source: MIT

    Source: MIT

    Source: MIT

    For further reading on the mechanical properties of AM metals, you may consult: