Following on from 17-4 PH Stainless Steel and 316L Stainless Steel, Desktop Metal has now rolled out their third material, H13 Tool Steel, for use with the Studio System’s Bound Metal Deposition (BMD) technology.
Known for its exceptional general hardness and toughness, abrasion resistance, and stability in heat treatment, H13 Tool Steel is widely used in a variety of either hot or cold work applications.
- Mold inserts
- Extrusion dies
- Forging dies
- Sheet metal tooling
- Stamping tools
The high hardness and toughness of H13 makes it particularly difficult to machine using traditional methods, and often requires specialty holders, cutting tools, low feed rates, and conditions, which are time-consuming and costly.
Through the BMD process, H13 tools can not only be fabricated quickly but also potentially feature complex geometries that were achievable or difficult to accomplish through machining (e.g., molds with conformal cooling channels). This geometric freedom makes printing complex H13 parts particularly advantageous with the Studio System.
Application Example #1 – Mouthpiece injection mold core
Shops commonly use Master Unit Dies (MUD’s) to produce plastic components in high volume using injection molding. These MUDs utilize swappable mold inserts to provide and core and cavity of the part being molded.
But the high hardness and toughness of H13 makes it extremely difficult to machine, resulting in long lead times, high part costs, and accelerated wear on end mills and drills.
Through metal 3D printing, near-net-shape of the part can be achieved quickly with only a final secondary operation finishing pass required. 3D printing also enables the incorporation of a conformal cooling channel that greatly increases the cooling rate of the mold to reduce the mold’s cycle time drastically and allow more parts to be molded hourly.
The H13 3D printed mold will also last for a longer time compared to other mold materials.
Application Example #2 – Extrusion Die
Used for the extrusion of framing materials amounting to different lengths according to requirements, the die has to withstand extreme temperatures and pressures during the extrusion process.
However, the complex lofted geometry means it is difficult to machine, especially when it’s made of tool steel. This difficulty also results in long lead times and high costs, which limits the number of iterations.
By 3D printing the die with BMD, different design iterations can be performed quickly and affordably. The reduced part cost also enables cost-effective short runs that were not economical previously. With the known excellent characteristics of H13, one can expect the die to operate as intended and expect a long lifespan with it.
Application Example #3 – Zipper Mold
Millions of zippers are manufactured every second, with die casting being the primary manufacturing method for metal zippers. To achieve a low target cost per part, zippers are often produced in high volumes.
However by adopting 3D printing, manufacturers can produce custom mold inserts to die-cast zippers specifically for low volume applications and enable many different designs to be produced.
With the capabilities of 3D printing, this mold is able to feature many fine details such as logos, textures, and subtle draft angles that are critical for the part’s molding success, with the use of DM’s high-resolution 250μm nozzle. There were also valuable time and cost savings as opposed to using traditional manufacturing methods.
Because of thermal fatigue cracking (heat checking) concerns due to repeated heating and quick cooling processes, H13 was highly suitable for this mold because of their hot hardness and abrasion resistance. The material’s high toughness also meant that it had a longer lifespan when compared to alternatives.
H13 Tool Steel joins 316L and 17-4PH as core materials available for use with the Studio System now. Three other core materials – Alloy 625, Copper, and AISI 4140 – are currently being developed.