Hand rubbing nuclear fusion live in the wilderness

Chapter 399 Robot Joint Materials

Using 3D printing technology, industrial robots can be manufactured quickly and in large quantities, which can make up for labor vacancies in a relatively short period of time.

But relatively speaking, the 3D printing technology currently used in various countries also has many shortcomings.

The first is the material problem, which is also a problem that the Korean won needs to solve.

3D printing technology has been developed for more than ten years since it was proposed, and has many advantages, but there are also many disadvantages.

The biggest limitations and shortcomings are mainly reflected in the materials, and the materials that can be used for 3D printing are very limited.

For the current human society, 3D printing materials are mainly plastics, resins, gypsum, ceramics, sand and metals.

Among them, materials that cannot stabilize their own shape, such as metal and fine sand, are rarely used to print objects, because even if they are printed, the formed objects have no other use other than being used as a model.

Although countries have developed many homogeneous and heterogeneous materials for 3D printing, for countries with huge demand for materials, the materials that can be used for 3D printing are still very limited.

And with the materials that can currently be printed, there is very little that 3D printing technology can do.

Therefore, the need to develop new materials still exists, especially in the printing of metal materials, which is not possible for a few companies in several countries.

If metal material printing is still barely able to be done by a few countries and companies, then there are two fatal flaws.

The first one is that 3D printing technology is not yet able to print movable objects.

Not even a small [-]WD.

The reason is divided into two parts, one is that the printing materials are not qualified, and the other is technical problems including printing accuracy, printing quality, computer programming, model design, etc.

The combination of the two leads to the inability of the current popular 3D printing technologies in various countries to print movable items.

The second defect is that most of the items printed by 3D printing technology cannot meet the actual use requirements of the project, whether it is physical properties, chemical properties, or its accuracy.

At present, almost all the printed parts cannot be used as functional parts, and can only be used as prototypes.

For example, if you want to manufacture a car, you can accurately manufacture its model through 3D printing technology, but the printed car cannot be driven.

Even if a part of the car is broken, it cannot be replaced with a part printed by 3D printing technology.

This is because the parts printed by 3D printing technology are not up to standard in terms of physical strength, stiffness, fatigue resistance and other properties.

In addition, because 3D printing adopts the additive manufacturing process of "layer-by-layer manufacturing and layer-by-layer superposition", no matter how closely the layers are combined, it cannot be compared with parts cast from traditional molds.

The microstructure and structure of a part material determine the performance of the part.

Therefore, the things printed by the current 3D printing technology do not have any wide practicability except for molds and individual purposes.

But no matter which of the above problems, in the final analysis, it is actually caused by the poor quality of the printed materials.

If the problem of printing materials can be solved, these problems can basically be solved.

This is why KRW has set its sights on 3D printing technology.

Large-scale 3D printers or large-scale 3D printing factories are a way for future industrial cluster manufacturing.

This road can realize unmanned management, which greatly saves manpower.

Because 3D printing technology can use computers to directly produce various parts or models without the assistance of other equipment.

This is different from traditional factories. ,
When a traditional factory produces parts, it needs many devices or even multiple production lines to cooperate to complete the assembly.

However, 3D printing technology does not require assembly, which is not only faster, but also saves a lot of manpower and material costs, and improves production efficiency.

Of course, 3D printing technology is still a new emerging technology, with obvious advantages and disadvantages.

What the Korean won has to do is try its best to make up for its shortcomings.

In the studio, Han Yuan picked up a pencil and wrote on the white paper the materials needed for 3D printing technology.

For him, this material must have sufficient strength, toughness, resistance, corrosion resistance and other excellent properties.

Because this is used to make industrial robots.

Composite carbon fiber material, cobalt chromium alloy, acrylic material, titanium alloy, resin.
A series of materials that are relatively suitable for 3D printing technology are listed on the paper by Won.

After writing, Han Yuan put down the pencil in his hand and picked up the paper.

Manufacturing industrial robots through 3D printing technology requires more than one material.

From main skeleton to power supply, to wireless communication to intelligent control.
There are countless parts on an intelligent industrial robot, and the functions of each area are different, which require completely different materials to manufacture.

But what the Korean won wants is just one of the key materials.

That is the 3D printing material that can be used in joints.

If you leave aside the programming aspects of software programs and control systems, it can be said that more than half of the performance of a robot depends on the joint activities.

That's right, the joints of a robot are so important.

The degree of freedom of movement and redundant degrees of freedom at the joints determine the flexibility, degrees of freedom, motion accuracy, motion characteristics, dynamic characteristics, etc. of the robot.

The human arm (big arm, forearm, wrist) is flexible enough because there are a total of seven degrees of flexibility, which is enough to support humans to complete most of the work.

Moreover, compared with material parts in other parts, the parts at the movable joints of the robot are under greater pressure, and the performance requirements for the materials used are higher.

If most of the materials of a robot can be made of high-strength and high-toughness composite carbon fiber materials, then the materials at the joints cannot use carbon fiber materials.

Because the surface of the carbon fiber material printed by 3D printing technology is quite rough, and the material at the joint requires a smooth surface to a certain extent, the carbon fiber material cannot meet the requirements.

As for various alloy materials, although the smoothness can meet the requirements after treatment, the strength and fatigue resistance of these two materials cannot meet the requirements if they are processed by 3D printing technology.

After all, compared with the traditional smelting technology, the alloy printed by 3D printing technology is weaker in terms of strength and toughness by more than one grade.

Therefore, developing a material for robot joints that can be used for 3D printing is the purpose of Won this time.

Compared with the materials used in ordinary smelting processes, the materials used in 3D printing technology have higher requirements.

Just like powder metallurgy, it can basically be carried out using powders below one millimeter.

Of course, there are also some ultra-fine particle powder metallurgy technologies that require the diameter of the powder particles to be about [-] microns or less.

However, this is a relatively special situation. Generally speaking, the particle diameter of the powder used is relatively large.

However, the basic requirements for the diameter of powder particles used in 3D printing metal materials are all below [-] microns, and the strict requirements even reach about [-] microns.

In addition to the particle diameter of the metal powder, 3D printing technology has certain conditions for the high purity, sphericity, wide and narrow particle size distribution, and high or low oxygen content of the metal powder.

These conditions are more stringent than conventional powder metallurgy technology.

Staring at the various materials listed on the paper, Han Yuan fell into deep thought.

The knowledge of various material properties in the brain is invoked one by one to check and deduce, looking for materials suitable for 3D printing.

After a while, Han Yuan woke up from his contemplation, and wrote down the names of the other two materials on the paper again.

【Amorphous Alloy Material】【Eutectic Alloy Material】

The former is an alloy obtained by ultra-rapid cooling and solidification after the alloy material is proportioned, so that the atoms do not have time to arrange and crystallize in an orderly manner when the alloy is solidified.

The amorphous alloy material has a disordered structure, and the molecules that make up its substance do not have the grains and grain boundaries of the crystalline alloy.

During the third-level mission before, Han Yuan made this material.

The 'ion electric field' generator inside the electric propulsion without working medium engine uses the amorphous alloy material.

Another kind of 'eutectic alloy material' is an alloy material produced through the eutectic reaction of materials.

The so-called eutectic reaction refers to the reaction in which a liquid of a certain composition crystallizes two solid phases of a certain composition at a certain temperature at the same time.

In this reaction, the two solid phases generated by the material mechanically mix together to form a basic structure with a fixed chemical composition.

For example, an iron-carbon alloy with a carbon content of 2.11%-6.69% undergoes a eutectic reaction at a constant temperature of 1148°C, and the product is a mechanical mixture of austenite and cementite.

This carbon-iron alloy is called a "ledeburite" alloy.

Eutectic alloy materials have a very special place.

That is, the eutectic temperature of the eutectic alloy is lower than the melting point of any of the metals that make it up.

Such as iron-nickel eutectic alloy materials.

Among them, the melting point of iron is 1538 degrees Celsius, while the melting point of nickel is 1453 degrees Celsius.

Then the melting point of the formed iron-nickel eutectic alloy is about 1350 degrees.

Because the melting point of the constituent metal in the eutectic alloy is about [-] degrees different from its melting point in the pure metal state.

Therefore, the vast majority of eutectic alloys can directly change from solid to liquid when the temperature is raised.

Instead of going through the plastic stage like ordinary metals or alloys.

This point has been widely applied to alloy smelting and metal heat treatment industries.

When writing 3D printing materials just now, Won did not think about the smelting methods of these two alloys.

The main reason is that their smelting methods are relatively special and not suitable for powder metallurgy.

However, after careful consideration, Won still added these two alloy materials.

Not just adding, he also focused on the smelting methods of these two alloy materials.

Conventional powder metallurgy metal and 3D printing technology have actually been explored by scientists from various countries in reality.

There is no way to find, sometimes it may be very hidden, sometimes it may be right under the eyes of people.

Won decided to try the two roads of amorphous alloy materials and eutectic alloy materials.

When the eutectic alloy material is solidified, it does not solidify in a paste state, but directly becomes a solid state, so as long as the solidification sequence is well controlled, shrinkage cavities and porosity rarely occur.

This is actually very suitable for 3D printing technology.

Especially in the manufacture of joints, the surface of the formed joint parts will be quite smooth, and will not form various uneven places or burrs.

Amorphous alloy materials have many unique properties.

Such as excellent magnetism, corrosion resistance, wear resistance, high strength, hardness and toughness, high resistivity and electromechanical coupling performance, etc.

Won would like to try to combine the advantages of eutectic alloy and amorphous alloy.

Late at night, the hot and dry air was taken away by the evening breeze, and a cool fresh breeze was brought in by the way.

Han Yuan sat in the studio, with a pencil in his hand, he kept writing one item after another of commonly used metal materials on the white paper.

Most of the listed metal materials only stayed on the paper for ten seconds before being marked with X's.

The won is excluding inapplicable metal materials one by one, and putting suitable metal materials aside.

The exclusion of this alloy material is mainly based on the difference in easy solution and whether there is a huge difference in the melting points of the two.

Just like tin, a metal with a melting point of only 230 degrees, obviously cannot get together with tungsten, which has a melting point as high as [-] degrees.

The difference between the melting points of the two is too large, so it is not suitable for the smelting of amorphous alloy materials.

Although the overall melting point of the amorphous alloy material is lower than any of the alloys, when the melting points of the two metal materials in the alloy are too different, they will not form at all.

Therefore, you must first exclude metal materials with a large difference in melting point, and try to choose a metal with a difference in melting point within [-] degrees for the first time.

Determine it first, and then analyze their easy solution difference and crystal structure difference.

Through the three points of melting point, difference in easy solid solution, and crystal structure, it is almost possible to roughly determine whether two metals or multiple metals can form amorphous alloys and eutectic alloys without doing experiments.

And when two metal materials can form amorphous alloy and eutectic alloy at the same time, South Korea will screen them out.

Just like this step by step, without going through any experiments, just relying on the physical properties of various metals, Won can do things that countries need to conduct many experiments to confirm.

Although there may be some errors, such as omitting some metals that can be both eutectic and amorphous, it is also possible to match some metals that cannot be matched together.

But compared to the huge advantage of not needing to experiment, this loophole is nothing.

The time saved is enough for Korean won to slowly re-screen the remaining metal materials.

(End of this chapter)