The risks involved in chasing leapfrog tech that's totally revolutionary is that all that time, money, and talent will go wasted with sometimes very little payoff. That's why it's easier and quicker to catch up and then maintain some lead in an established field of technology. These exotic and experimental propulsion are interesting but most projects are still focused on catching up when it comes to engines. Once that's done, maybe there's less risk to diversify the engineering talent.
Chinese Engine Development
- Thread starter jackbh
- Start date
The risks involved in chasing leapfrog tech that's totally revolutionary is that all that time, money, and talent will go wasted with sometimes very little payoff. That's why it's easier and quicker to catch up and then maintain some lead in an established field of technology. These exotic and experimental propulsion are interesting but most projects are still focused on catching up when it comes to engines. Once that's done, maybe there's less risk to diversify the engineering talent.
SamuraiBlue
Captain
The XF-9 will power the F-3. It is going through various test right now and will power the F-3 proto-type around 2026ish to be mass produced in 2030.
Maybe, but the risk of trying to catch up in an established field of technology is that you waste decades and still end up unacceptably behind because the market leaders were also advancing at the same time. I mean look at Russia. They are ahead of China in engine development and have been working on the Il-76/86/96 since the Cold War yet it still isn't competitive.
When there isn't much to lose, it might make sense to diversify. The advantage of new technology is that there isn't as much institutional knowledge and know-how built up from decades that you have to reproduce. And while it may also take decades to master, the end result is that you are actually ahead instead of still behind.
by78
General
This might become relevant in the future if further developed. Posting it here since there is no other appropriate thread I can find.
On Jul 24, 2020
Resolving alloys’ strength-ductility trade-off and thermal instability
Credit: Photo source: DOI number: 10.1126/science.abb6830
Intermetallic alloys potentially have high strength in a high-temperature environment. But they generally suffer poor ductility at ambient and low temperatures, hence limiting their applications in aerospace and other engineering fields. Yet, a research team led by scientists of City University of Hong Kong (CityU) has recently discovered the disordered nanoscale layers at grain boundaries in the ordered intermetallic alloys. The nanolayers can not only resolve the irreconcilable conflict between strength and ductility effectively, but also maintain the alloy’s strength with an excellent thermal stability at high temperatures. Designing similar nanolayers may open a pathway for the design of new structural materials with optimal alloy properties.
This research was led by Professor Liu Chain-tsuan, CityU’s University Distinguished Professor and Senior Fellow of the Hong Kong Institute for Advanced Study (HKIAS). The findings were just published in the prestigious scientific journal Science, titled “Ultrahigh-strength and ductile superlattice alloys with nanoscale disordered interfaces“.
Just like metals, the inner structure of intermetallic alloys is made of individual crystalline areas knows as “grains”. The usual brittleness in intermetallic alloys is generally ascribed to the cracking along their grain boundaries during tensile deformation. Adding the element boron to the intermetallic alloys has been one of the traditional approaches to overcome the brittleness. Professor Liu was actually one of those who studied this approach 30 years ago. At that time, he found that the addition of boron to binary intermetallic alloys (constituting two elements, like Ni3Al) enhances the grain boundary cohesion, hence improving their overall ductility.
A surprising experimental result
In recent years, Professor Liu has achieved many great advances in developing bulk intermetallic alloys (intermetallic alloy is also called superlattice alloy, constructed with long-range, atomically close-packed ordered structure). These materials with good strengths are highly attractive for high-temperature structural applications, but generally suffer from serious brittleness at ambient temperatures, as well as rapid grain coarsening (i.e. growth in grain size) and softening at high temperatures. So this time, Professor Liu and his team have developed the novel “interfacial nanoscale disordering” strategy in multi-element intermetallic alloys, which enables the high strength, large ductility at room temperature and also excellent thermal stability at elevated temperatures.
“What we originally tried to do is to enhance the grain boundary cohesion through optimizing the amount of boron,” said Dr Yang Tao, a postdoc research fellow at CityU’s Department of Mechanical Engineering (MNE) and IAS, who is also one of the co-first authors of the paper. “We expected that, as we increased the amount of boron, the alloy would retain ultrahigh strength due to its multi-element constituents.”
According to conventional wisdom, adding trace amounts (0.1 to 0.5 atomic percent (at. %)) of boron substantially improves their tensile ductility by increasing grain-boundary cohesion. When excessive amounts of boron were added, this traditional approach would not work. “But when we added excessive amounts of boron to the present multicomponent intermetallic alloys, we obtained completely different results. At one point I wondered whether something went wrong during the experiments,” Dr Yang recalled.
To the team’s surprise, when increasing boron to as high as 1.5 to 2.5 at. %, these boron-doped alloys became very strong but very ductile. Experiment results revealed that the intermetallic alloys with 2 at. % of boron have an ultrahigh yield strength of 1.6 gigapascals with tensile ductility of 25% at ambient temperatures.
By studying through different transmission electron microscopies, the team discovered that when the concentration of boron ranged from 1.5 to 2.5 at. %, a distinctive nanolayer was formed between adjacent ordered grains. Each of the grains was capsulated within this ultrathin nanolayer of about 5nm thick. And the nanolayer itself has a disordered atomic structure. “This special phenomenon had never been discovered and reported before,” said Professor Liu.
Their tensile tests showed that the nanolayer serves as a buffer zone between adjacent grains, which enables plastic-deformation at grain boundaries, resulting in the large tensile ductility at an ultrahigh yield strength level.
Why is the disordered nanolayer formed?
The team found that the further increase in boron has substantially enhanced the “multi-element co-segregation” – the partitioning of multiple elements along the grain boundaries. With the advanced three-dimension atom probe tomography (3D APT) at CityU, the only one of its kind in Hong Kong and southern China, they observed a high concentration of boron, iron and cobalt atoms within the nanolayers. In contrast, the nickel, aluminium and titanium were largely depleted there. This unique elemental partitioning, as a result, induced the nanoscale disordering within the nanolayer which effectively suppresses the fractures along grain boundaries and enhances the ductility.
Moreover, when evaluating the thermal response of the alloy, the team found that the increase in grain size was negligible even after 120 hours of annealing at a high temperature of 1050°C. This surprised the team again because most of the structural materials usually show the rapid growth of grain size at high temperature, resulting in strength decrease quickly.
A new pathway for developing structure materials for high-temperature uses
They believed that the nanolayer is pivotal in suppressing growth in grain size and maintain its strength at high temperature. And the thermal stability of the disordered nanolayer will render this type of alloy suitable for high-temperature structural applications.
“The discovery of this disordered nanolayer in the alloy will be impactful to the development of high-strength materials in future. In particular, this approach can be applied to structural materials for applications at high-temperature settings like aerospace, automotive, nuclear power, and chemical engineering,” said Professor Liu.
On Jul 24, 2020
Resolving alloys’ strength-ductility trade-off and thermal instability
Credit: Photo source: DOI number: 10.1126/science.abb6830
Intermetallic alloys potentially have high strength in a high-temperature environment. But they generally suffer poor ductility at ambient and low temperatures, hence limiting their applications in aerospace and other engineering fields. Yet, a research team led by scientists of City University of Hong Kong (CityU) has recently discovered the disordered nanoscale layers at grain boundaries in the ordered intermetallic alloys. The nanolayers can not only resolve the irreconcilable conflict between strength and ductility effectively, but also maintain the alloy’s strength with an excellent thermal stability at high temperatures. Designing similar nanolayers may open a pathway for the design of new structural materials with optimal alloy properties.
This research was led by Professor Liu Chain-tsuan, CityU’s University Distinguished Professor and Senior Fellow of the Hong Kong Institute for Advanced Study (HKIAS). The findings were just published in the prestigious scientific journal Science, titled “Ultrahigh-strength and ductile superlattice alloys with nanoscale disordered interfaces“.
Just like metals, the inner structure of intermetallic alloys is made of individual crystalline areas knows as “grains”. The usual brittleness in intermetallic alloys is generally ascribed to the cracking along their grain boundaries during tensile deformation. Adding the element boron to the intermetallic alloys has been one of the traditional approaches to overcome the brittleness. Professor Liu was actually one of those who studied this approach 30 years ago. At that time, he found that the addition of boron to binary intermetallic alloys (constituting two elements, like Ni3Al) enhances the grain boundary cohesion, hence improving their overall ductility.
A surprising experimental result
In recent years, Professor Liu has achieved many great advances in developing bulk intermetallic alloys (intermetallic alloy is also called superlattice alloy, constructed with long-range, atomically close-packed ordered structure). These materials with good strengths are highly attractive for high-temperature structural applications, but generally suffer from serious brittleness at ambient temperatures, as well as rapid grain coarsening (i.e. growth in grain size) and softening at high temperatures. So this time, Professor Liu and his team have developed the novel “interfacial nanoscale disordering” strategy in multi-element intermetallic alloys, which enables the high strength, large ductility at room temperature and also excellent thermal stability at elevated temperatures.
“What we originally tried to do is to enhance the grain boundary cohesion through optimizing the amount of boron,” said Dr Yang Tao, a postdoc research fellow at CityU’s Department of Mechanical Engineering (MNE) and IAS, who is also one of the co-first authors of the paper. “We expected that, as we increased the amount of boron, the alloy would retain ultrahigh strength due to its multi-element constituents.”
According to conventional wisdom, adding trace amounts (0.1 to 0.5 atomic percent (at. %)) of boron substantially improves their tensile ductility by increasing grain-boundary cohesion. When excessive amounts of boron were added, this traditional approach would not work. “But when we added excessive amounts of boron to the present multicomponent intermetallic alloys, we obtained completely different results. At one point I wondered whether something went wrong during the experiments,” Dr Yang recalled.
To the team’s surprise, when increasing boron to as high as 1.5 to 2.5 at. %, these boron-doped alloys became very strong but very ductile. Experiment results revealed that the intermetallic alloys with 2 at. % of boron have an ultrahigh yield strength of 1.6 gigapascals with tensile ductility of 25% at ambient temperatures.
By studying through different transmission electron microscopies, the team discovered that when the concentration of boron ranged from 1.5 to 2.5 at. %, a distinctive nanolayer was formed between adjacent ordered grains. Each of the grains was capsulated within this ultrathin nanolayer of about 5nm thick. And the nanolayer itself has a disordered atomic structure. “This special phenomenon had never been discovered and reported before,” said Professor Liu.
Their tensile tests showed that the nanolayer serves as a buffer zone between adjacent grains, which enables plastic-deformation at grain boundaries, resulting in the large tensile ductility at an ultrahigh yield strength level.
Why is the disordered nanolayer formed?
The team found that the further increase in boron has substantially enhanced the “multi-element co-segregation” – the partitioning of multiple elements along the grain boundaries. With the advanced three-dimension atom probe tomography (3D APT) at CityU, the only one of its kind in Hong Kong and southern China, they observed a high concentration of boron, iron and cobalt atoms within the nanolayers. In contrast, the nickel, aluminium and titanium were largely depleted there. This unique elemental partitioning, as a result, induced the nanoscale disordering within the nanolayer which effectively suppresses the fractures along grain boundaries and enhances the ductility.
Moreover, when evaluating the thermal response of the alloy, the team found that the increase in grain size was negligible even after 120 hours of annealing at a high temperature of 1050°C. This surprised the team again because most of the structural materials usually show the rapid growth of grain size at high temperature, resulting in strength decrease quickly.
A new pathway for developing structure materials for high-temperature uses
They believed that the nanolayer is pivotal in suppressing growth in grain size and maintain its strength at high temperature. And the thermal stability of the disordered nanolayer will render this type of alloy suitable for high-temperature structural applications.
“The discovery of this disordered nanolayer in the alloy will be impactful to the development of high-strength materials in future. In particular, this approach can be applied to structural materials for applications at high-temperature settings like aerospace, automotive, nuclear power, and chemical engineering,” said Professor Liu.
SamuraiBlue
Captain
I think some people needs to chill for a moment. (Not towards the above article bt people talking about battle with the US in another thread)
It&s actually nothing new we known about this for a while now. It's not about the future but where we stand now.
It&s actually nothing new we known about this for a while now. It's not about the future but where we stand now.
From the article you cited -
Initial production models of China’s latest J-20 stealth fighter used the upgraded WS-10B, .
Do you think this statement is factually correct?
J-20 is also unable to supercruise, meaning it must use afterburner to reach supersonic speeds. China’s premier air superiority fighter will struggle to keep up with its 5th generation contemporaries until the situation is rectified.
How many 5th generation fighter jets can actively supercruise? How many active production 5th Gen Fighter jets are there in fact? To me, there exists only three - F22, F35 and J20.
Of these only F22 and J20 are designed to be supercruise. Only F22 can do supercruise.
Edit : F22 isn't "active" production. Until and unless they bring back the whole tooling and production line with a token 10-20 Billion investment.
I've been hearing about Ball point pens, China and the equations it tries desperately to make up to point at China's supposed lag with overall tech development for long.
It's is as tiring as hearing Japan is "high tech" while still being reliant on Fax machines and a society that hasn't moved much from the peak of 1980s Bubble Era.
Maybe the author Lewin Day should stick with reporting on Cheap electronics and Home Appliances.
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SamuraiBlue
Captain
Yeah , yeah once PRC is able to develop composites like CMC, Transparent Ceramic and/or, High modulus Carbon fiber like HR40 (which was all developed independently by Japan) then we may listen but till then its all bark with no bite.
I think his point was to say that China not being able to make ball bearings suitable and cost effective enough for cheap/affordable ballpoint pens is not indicative of anything. It's like saying Germany doesn't have a real space industry and comprehensive set of space technologies so therefore Germany must be a technologically weak nation. A totally foolish thing.
China never had a reason to develop a suitable and cost effective ballpoint steel bearing. It only took 5 years to achieve similar results when they did bother only due to some sort of political/ego motivation. The real engineering challenge here was controlling costs and creating a manufacturing program that was as cost and resource efficient as those from where the bearings were sourced. Making ballpoint bearings is easy as piss if you really want to do it without consideration for finances. There are plenty of high end Chinese bearings for other industrial applications which are pretty much on par with the best albeit at almost equal costs. It's just difficult to achieve a certain consistency and low failure rate under a certain price. Ironically this is how China dominates so many areas of manufacturing over other technologically capable countries - it offers the best net balance. When it came to ballpoint bearings, that just happened to be one area where non-Chinese sources were superior. There are plenty of other examples.
Chinese didn't make ballpoint bearings, Switzerland doesn't make GIS/GNS systems, Japan doesn't make nuclear weapons, Russia doesn't make high end IC, France doesn't make supercomputers etc etc... I think the ballpoint bearing analogy used by the author of that article misses the point entirely especially considering how he applied it. Okay maybe the idea was to say that engines aren't quite an engineering problem equivalent to controlling the cost of ballpoint bearings. Still I think you missed Xsizor's point. Japan is a technologically capable nation (consistently a leader) and yet there are situations where it can be made to seem otherwise such as the prevalence of cassette tapes and other "strange" anachronisms. We all know it would be foolish and untrue to use that as some sort of evidence that Japan isn't a tech dominant nation. Similarly talking about China's past "inability" to make ballpoint bearings is stupidly misunderstanding why. Surely it's at least been proven it wasn't an issue of ability but rather one of simple economics.
Anyway how any of this truly is useful for presenting his points about difficulty manufacturing engines is lost on me. Probably why I'm not a journalist who's writing about things he's got no business understanding. I'm sure publications can find engineers who can write these articles. Maybe those guys just have much better and worthwhile things to do
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What was the point of this post? we all know that china lags in aircraft engine tech.
manqiangrexue
Brigadier
Oh please, everything Japan does is under the permission and as a vassal of the United States. Japan got a head start by rolling over (but then again, it didn't have much of a choice). When Japan put up a small economic challenge to the US, it was crushed like a potato chip. Regardless of your few cherry-picked examples, not the US, not the EU, nobody finds Japanese tech alarming today because it is like a settled old man. Meanwhile, the Western world tosses and turns with panic and helpless angst, often causing internal harm with its desperation, at the rise of Chinese technology expanding like a young forest with new sprouts and surprises blooming everyday. So save the bark for yourself; it is for a leashed country like Japan. When China softly clears its throat, the world trembles at the roar.
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