Customers and peers often ask us these questions: What is binder jet 3D printing? What is 3DP technology? What is droplet jet 3D printing? Compared with other mainstream technologies on the market, what are their advantages and disadvantages? Now I will share what I understand and understand for your reference.
What is binder jet 3d printing technology?
Binder jet 3D printing is also called droplet jet 3D printing, inkjet 3D printing, or 3DP. The binder jet 3D printing process is similar to the traditional 2D inkjet printer, and it is one of the molding technologies that closely fits the concept of "3D printing". It was first developed by the Massachusetts Institute of Technology (MIT) in 1993. This technology uses nozzles to spray binders to selectively bond powders to form.
As shown in the above figure, first, the powder spreading mechanism accurately spreads a thin layer of powder material on the processing platform, and then the inkjet print head sprays a layer of binder on the powder according to the cross-sectional shape of this layer, spraying it to the thin layer of the binder. The layer powder solidifies. Then spread a layer of powder with a certain thickness on this layer, and the print head sprays binder in the shape of a cross section. So layer by layer, from bottom to top, until all the layers of a part are printed. Then the uncured powder is cleaned up and a three-dimensional physical prototype is obtained. This is what we call the binder jet 3D printing technology.
The main advantages of binder jet 3D printing compared to other mainstream 3D printing
Through the principle of binder jet 3D printing, we can analyze its advantages:
● Wide range of raw materials
First of all, theoretically speaking, binder jet 3D printing can print all powders that can be bonded by binders, that is, almost all powders that can be bonded are its molding materials. However, due to the limitations of raw material powder and binder development, currently the relatively mature molding materials on the market are only gypsum powder (which can achieve full-color printing molding), sand, metal powder, and ceramic powder. We believe that as everyone pays more and more attention to binder jet 3D printing in the future, the wide range of raw materials will become more and more obvious.
● High speed
Compared with several mainstream 3D printing technologies currently on the market, such as SLS, SLM, SLA, FDM... Because the binder jet relies on array nozzles to spray the binder, our nozzles are all wide. Unlike lasers or other nozzles, which are all a "point", the binder jet technology is a "line-to-surface" scanning" bonding, which is naturally faster than other "point-to-surface" methods. Generally speaking, it will be dozens of times or even 100 times faster! And with the development of sprinkler technology, the width of sprinklers is getting bigger and bigger, and the characteristics of fast speed will become more prominent.
● Low printing environment requirements, low comprehensive use cost
For example, some existing 3D printing technologies currently use some specific environmental requirements, such as adding protective gas, heating, airtight environment..., and binder spraying generally does not require a special environment.
And the comprehensive use cost shows many advantages. For example, binder jet 3D printing equipment does not require expensive devices such as lasers and scanning systems, and does not require too many morphological requirements for powder materials. Generally, there is no need for support in the printing process.
The lack of binder jet 3D printing
● The strength of initially formed part is not high
Since the binder jet 3D printing is bonded layer by layer with binder, the initial strength is not high. But I personally think that this problem can often be improved or solved through post-processing. For example, we can use high-temperature sintering to strengthen the overall strength and performance of the metal parts.
● The surface quality of the initially formed parts is relatively low
Since the binder jet 3D printing is cold forming, there may be floating powder. In fact, this problem can also be accomplished through simple post-processing. For example, the surface roughness of the metal parts we printed after high-temperature sintering is relatively better.