Does the strength and toughness of metal printing materials meet industrial requirements?

1. A big change in how materials work: going from "usable" to "optimal"
There has been a big improvement in the strength of metal 3D printing materials. For example, the parts made by the selective laser melting (SLM) process using the In718 nickel-based alloy that is often used in the aviation industry have a tensile strength of up to 1200MPa and a yield strength of 1050MPa. This is better than the traditional casting process (tensile strength of about 900MPa) and even close to the level of forgings (tensile strength of about 1150MPa). After 20 heat cycle testing, the titanium alloy combustion chamber that Platinum Lite printed for a certain type of rocket engine has a high-temperature strength retention rate of 92%, which is much higher than the 85% norm that the industry requires.
The gradient heat treatment technology that MIT came up with has set a new standard for the industry when it comes to making things more durable. By carefully controlling the cooling rate, this technology increases the impact toughness of 3D printed In713 high-temperature alloy at 927 °C from 15J/cm² to 28J/cm². The fracture toughness (KIC) reaches 65MPa·m ¹/², which meets the needs of aircraft engine turbine blades in very high-temperature environments. This ability to manage microstructure lets 3D printing materials keep their strength while losing only 40% of their toughness compared to previous methods.
The better material database gives data support for making things work better. Platinum Technology's intelligent process library has gathered more than 2000 sets of material parameters. These parameters span 12 common industrial metals, such as titanium alloys, nickel-based alloys, and stainless steel. By changing the laser power (180–220W), scanning speed (800–1200mm/s), and layer thickness (30–50 μ m), it is possible to precisely control the tensile strength between 980 and 1150MPa and the elongation between 12 and 18%. This meets the needs of a wide range of applications, from orthopedic implants to aerospace structural components.
2. Process innovation: finding a way to balance strength and toughness
The multi-laser collaborative scanning technology fixes the problem of uneven strength in big portions. Leiming Laser's LiM-X400M equipment uses three laser seamless splicing technology to keep the strength of items in the size range of 300mm × 400mm × 350mm within ± 3%. This technology combines six parts that used to need to be welded and put together into one whole in the satellite bracket that was produced for a certain aerospace firm. This makes the fatigue life go from the customary 8000 cycles to 25000 cycles.
Unsupported printing technology greatly enhances the mechanical performance of suspended structures by optimizing the dynamics of the melt pool. Xi'an Ouzhong Technology's variable energy density scanning approach has made suspended structures with printing angles less than 45 ° 20% stronger. This approach combines the original 12 process holes into 3 continuous flow channels in the valve block produced for underwater special equipment. This cuts the volume by 60% and the pressure loss by 25%. The wall thickness of the flow channel is accurate to within ± 0.05mm.
The intelligent monitoring system has made it possible to optimize process parameters in real time. XX Automobile uses an AI-based melt pool monitoring system that can change the laser intensity and scanning path on the fly. This lowers the porosity from the industry average of 0.3% to less than 0.05%. The technique made the topology-optimized structure 15% stiffer and 25% lighter when printing the electric engine hood. It passed the tough test of 2100 Newton meters of torque.
3. Industrial scenario verification: going from the lab to the production line
The use in the aerospace area is the most persuasive. By using 3D printing technology, GE produced the LEAP engine fuel nozzle, which combines 20 separate parts into one unit. This makes it 25% lighter and 15% more fuel efficient. The total number of items delivered has gone beyond 500,000. After 1000 hours of testing at extreme temperatures, China Aviation Industry Corporation (AECC) found that 3D printed turbine guide blades were 18% better at cooling and lasted three times longer than traditional cast blades.
The need for better materials in the energy and power business is pushing scientists to make new discoveries all the time. Maxwell Medical, a smart manufacturing company in Xi'an, made a 3D-printed photovoltaic equipment titanium alloy flow channel plate that evenly distributes cooling liquid through a micrometer-level flow channel design. This keeps the temperature of the single crystal furnace within ± 0.5 °C and saves 12% energy compared to traditional machined products. In the use of nuclear reactor cooling systems, 3D printed flow channel heat exchangers have been shown to be 20% more efficient at transferring heat, 40% less material is used, and they have passed 10 years of accelerated life testing.
The need for medical implants to be both biocompatible and mechanically adaptable has led to new materials being developed. The 3D-printed porous titanium alloy interbody fusion device made by Sino Power has a porosity of 70% and an elastic modulus that is the same as that of human cortical bone (10–15GPa). Clinical response indicates a 60% improvement in bone development compared to standard implants three months post-surgery. The collaborative design of material structure function has improved the five-year survival rate of 3D printed implants from 85% to 97%.