Selecting a Metal for 3D Printing
Below we list the main properties and applications of each metal we have currently available for the Metal X system, along with a summary of heat treatment for each material. Heat treatment is a method of manipulating the material properties of certain types of steel to alter the ductility, toughness, hardness, and strength of a metal part. Those treated at higher temperatures typically have lower strength and hardness, but higher ductility and toughness. While specific properties may vary depending on part size and complexity, parts in the annealed condition have the highest ductility and are easiest to work with. For more specific details, reference our data sheet or other heat treating guides.
17-4 PH Stainless Steel
17-4 PH Stainless Steel is a common martensitic stainless steel characterized by high strength and excellent corrosion resistance. The material can be precipitation hardened to adjust mechanical properties to fit your application. This easy-to weld, versatile steel is widely used in the metalworking, aerospace, petrochemical, and medical industries.
Heat Treatment Information
Post-sintered 17-4 PH Stainless Steel is in a near-annealed state that can be easily worked with. Annealing to Condition A is only necessary if a part needs re-treatment. To heat treat, heat the part to the temperature and for the time span listed in the table below based on the desired condition. The data is based on wrought values, not printed, so final properties may differ. Post-sintered 17-4 does not need annealing prior to treatment. All parts should be air cooled.
H13 Tool Steel
H13 Tool Steel is a hot-work class steel characterized by high temperature hardness and abrasion resistance. It’s tough, impact resistant, and easy to machine and polish. H13 is resistant to thermal fatigue and premature heat-checking, and has excellent through-hardening properties, making it a great fit for molding applications like inserts, cores, and dies.
Heat Treatment Information
1. Anneal: H13 is not annealed when sintered and will need to be before heat treatment or machining. Heat the part to 1553-1652°F (845-900°C) at 400°F (222°C) per hour and hold at temperature for one hour per inch of maximum part thickness. Cool slowly at a rate not exceeding 50°F (28°C) per hour until 1000°F (538°C), then continue cooling in air. The hardness of annealed material should be around 90-95HRB.
2. Preheat: Use a double preheat to minimize distortion by heating the part at 400°F (204°C) per hour to 1100-1250°F (593-677°C) and letting the part equalize, then heat to 1500-1600°F (816-871°C) and equalize again.
3. Austentize: Heat rapidly to 1800-1890°F (982-1032°C) and hold for 30 minutes to 2 hours. Use a salt bath or controlled atmosphere furnace to minimize decarburization.
4. Quench: Quench the part in still air. Temper immediately after quenching. You may use an interrupted oil quench to below 150°F (65°C) on large parts or to maximize hardness and toughness, but there is some risk of cracking during the process.
5. Temper: Temper at a minimum of 50°F (28°C) above the maximum operating temperature of the part, using the table below as a guide. Temper at one hour per inch of maximum part thickness for at least two hours. A second temper at 25-50°F (14-28°C) below the first is recommended, especially when heat checking is a problem.
Markforged has other materials currently in testing, including stainless steels, tool steels, and other specialty metals. You can learn more about other metal 3D printing materials in our overview of 3D Printing Metal Filaments and Powders.