Will the mold industry use titanium alloy for 3D printing?

一, The technological benefits of 3D printing using titanium alloy and how well it works with mould needs
1. The ability to make complicated structures
Every day, the mould industry needs more and more complicated internal flow channels and lightweight lattice structures. However, standard processing methods are constrained by tool paths and mould design, which makes it hard to make high-precision complicated structures. With titanium alloy 3D printing, you can stack materials layer by layer to make three-dimensional models. This lets you make interior channels, thin-walled structures, and irregular cooling channels that older methods can't. For instance, in injection moulds, conformal cooling channels can cut the injection cycle by 30% to 50% and make the product yield better. Titanium alloys, like XM-7 mould steel, have a high thermal conductivity of 30W/(m · K), which makes them even better at cooling and makes them perfect for high-end moulds.
2. Benefits of material performance
Titanium alloys are strong and light, which can make moulds last longer and be easier to use. For example, 1.2709 (18Ni300) martensitic ageing steel has a tensile strength of 2000MPa and a hardness of 50–52HRC. It is good for high-stress die-casting moulds and lasts more than three times longer than regular H13 steel. Also, titanium alloys' resilience to corrosion (like how stable 316L stainless steel is in humid situations) can cut down on the number of times moulds need to be cleaned and lessen the cost of using them over time.
3. Personalisation and quick changes
A lot of the time, making a mould means doing a lot of experiments and changes, and traditional methods take a long time and cost a lot. Digital models can be used to directly create titanium alloy 3D printing, and mould prototype production and verification can be done in just a few days. This cuts down on the time it takes to do research and development. For example, a company that makes car parts uses titanium alloy 3D printing to cut mould creation time from 8 weeks to 2 weeks and make moulds 30% lighter by designing them with a lattice structure. This saves energy and makes the process easier to run.
二, Common ways that titanium alloy 3D printing is used in the mould industry
1. Moulds for injection
Because titanium alloy has a high heat conductivity and is resistant to corrosion, it is the best material for injection moulds. For instance, in car interior moulds, moulds made using 316L stainless steel powder and SLM technology, along with a conformal cooling water channel design, cut the injection moulding cycle from 120 seconds to 75 seconds and raise the yield rate to 98%. Also, titanium alloy moulds are great at polishing surfaces, which is important for making high-precision items like optical lenses.
2. Moulds for die casting
Die casting moulds have to be able to handle high-temperature metal liquid erosion and thermal stress cycles. Titanium alloys' resistance to thermal cracking and wear can greatly increase the life of the mould. After heat treatment, the aluminium alloy die-casting mould printed with 1.2709 powder has a hardness of 50HRC and stays structurally sound after 60,000 die-casting cycles. This is a 200% increase in service life compared to typical H13 steel moulds.
3. Mould for rubber tires
The wear resistance and thermal stability of titanium alloy can improve the accuracy of rubber moulds when they are used to make patterns. The CX (Corrax) stainless steel powder mould made with SLM technology has a polishing performance rating of A2. The lattice support structure cuts the mold's weight by 30% and improves the accuracy of pattern reproduction to within 0.01mm, which is what high-end tires need.
4. Moulds for medicine
The fact that titanium alloy is biocompatible provides it a particular edge in the realm of medical moulds. For instance, 3D printed titanium alloy bone plate moulds may be customised for each patient by making mould models directly from their CT data. This cuts down on the time needed to prepare for surgery and makes implants more adaptable.
三, Problems that titanium alloy 3D printing faces in the mould business
1. The cost of materials is high
The cost of titanium alloy powder is much higher than that of regular mould steel. For instance, 1.2709 powder costs roughly 800 yuan per kilogramme, which is three times more than 316L powder, which costs 260 yuan per kilogramme. Titanium alloy moulds last longer, but the high expense of making them in the first place makes it hard to use them on a big scale.
2. Keeping the process stable and fixing problems
There are problems with 3D printing titanium alloys, such as spheroidisation, cracks, and porosity, that make the mould less effective. For instance, in SLM technology, if the powder doesn't flow well enough, the layers won't bond well, and the components need to be better by changing the printing settings (like laser power and scanning speed) and the post-processing (like hot isostatic pressing).
3. Costs of equipment and post-processing
High-end titanium alloy 3D printers, like the EOS M400-4, cost more than 10 million yuan and need an inert gas protection system and a precise temperature control device. This makes them much harder to use. Also, titanium alloy moulds need to be treated once they are made, which adds to the cost and time it takes to make them.