Scientists Develop an Efficient Way to Produce Low-Cost Heatsinks

erek

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“Thermally stable composites obtained by the low-temperature carbonization of an elastomeric matrix filled with hard dispersed silicon carbide particles were obtained and investigated. Evolution of the microstructure and of mechanical and thermal characteristics of composites during thermal degradation and carbonization processes in a wide range of filling from 0 to 450 parts per hundred rubber was studied. For highly filled composites, the compressive strength values were found to be more than 200 MPa; Young’s modulus was more than 15 GPa. The thermal conductivity coefficient of composites was up to 1.6 W/(m·K), and this magnitude varied slightly in the temperature range of 25–300 °C. Coupled with the high thermal stability of the composites, the observed properties make it possible to consider using such composites as strained friction units instead of reinforced polymers.”


https://scitechdaily.com/scientists-develop-an-efficient-way-to-produce-low-cost-heatsinks/


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Neat. We have all experienced the thermal properties of silicon carbide in our TIMs, and I have always wondered how it would perform as a heatsink. We are on our way.
 
Rubber Heatsinks? What could go wrong?
I bet the thermal paste would be harder to remove.
 
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isn't it "Silicone Carbide" and not just strictly "Rubber"?

i personally didn't like when engine manufactures switched from Metal Intake Manifolds to Plastic, that's for sure...
Why? composite intake manifolds keep your intake air cooler by acting as an insulator without stupid aftermarket "spacers" - they're lighter and cheaper to produce.
 
Why? composite intake manifolds keep your intake air cooler by acting as an insulator without stupid aftermarket "spacers" - they're lighter and cheaper to produce.

Have you never taken an engine apart before? Plastic intake manifolds get just as hot or hotter than a metal manifold because engine coolant often runs through the manifold as it passes between cylinder banks. They often run hotter than metal intakes of the past because modern engines are so choked full of emissions shit, run hotter by design and prevent the escape of heat from the top of the engine like metal intake manifolds of the past.

Plastic and non-metal intake manifolds and other critical components are shit and have no business being on an engine. They warp, crack and literally disintegrate from the extreme heat and cold cycles, often requiring resealing or replacement after just a few years as they start leaking oil or pissing coolant everywhere. This includes leaking on to spark plugs often buried deep inside, causing oil fouling, misfires and dead cylinders.

Plastic intakes are cheaper to produce and cost the consumer more later in headaches and expensive repairs. Basically the car industry in a nutshell, make cheap shitty parts that rapidly fail and don't have replacements available, forcing people to buy new cars after just a few years because no parts are available.
 
Plastic intakes are cheaper to produce and cost the consumer more later in headaches and expensive repairs. Basically the car industry in a nutshell, make cheap shitty parts that rapidly fail and don't have replacements available, forcing people to buy new cars after just a few years because no parts are available.
That ring quite false to me, cars are used for more and more long time, even in rich country:

US-auto-cars-trucks-average-age-2017.png

In part because of how much better they got at easily running without much issue versus of those of the 70s/80s, now 10 year's car average Ford card even in place with bad winters like Canada can look new, when I was young a 10 year's old car was quite a story to start at minus 25/30 the morning, specially if it was not plug.

Most car get replaced out of preference than necessity in my experience. The car industry did remove as much metal as they could over time, but they still achieved to end up with cars that are used for much much longer/miles than in the past.
 
That ring quite false to me, cars are used for more and more long time, even in rich country:

View attachment 313734

Yes, cars are used for a longer period of time because people aren't buying newer cars, and especially newer trucks. New vehicles have such terrible reliability issues due to cutting corners and using pencil pushers for car design, rather than properly engineered cars.

In part because of how much better they got at easily running without much issue versus of those of the 70s/80s, now 10 year's car average Ford card even in place with bad winters like Canada can look new, when I was young a 10 year's old car was quite a story to start at minus 25/30 the morning, specially if it was not plug.

I have a 25 year old car and a 33 year old truck, both of which crank first time every time, even in very cold weather. Most problems easily fixed with a small ratchet set and a couple of screwdrivers. Can't say the same about a 3-5 year old Ford which will not start due to the PCM having fits and requiring multi-thousand dollar dealer tools to diagnose.

Most car get replaced out of preference than necessity in my experience. The car industry did remove as much metal as they could over time, but they still achieved to end up with cars that are used for much much longer/miles than in the past.

My buddy is a mechanic, and we've both seen numerous vehicles that were either irreparable due to parts not being available, due to cost or they just plainly don't exist. People definitely want their cars fixed and definitely don't want to buy a new vehicle, especially in the past year for obvious reasons.
 
I think the main reason people keep cars for a longer time now is that they can not afford new cars. The price of new cars has gone up a staggering ammount in the last 20 years. The average car is 20-30k now and trucks are even more expensive, and now you need a 10-15 year loan to pay for your car.
 
Let’s come clean guys. We don’t buy new cars because we keep buying $1000 video cards, which evidently soon will operate at 1600 C and have rubber ablative heat sinks that leave a plasma trail like a reentering Falcon 9.
yes to ablative heatsinks. I look forward to my future gaming laptop venting incandescent superheated gas out the exhaust, will really bring back nostalgia for the 290X days
 
My understanding of that heatsink was that the ran into limits of how much heat they could actually remove in non-lab settings.
 
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This reminds me of when I was researching metal foam heat sinks in the late 2000's. IIRC there was just too large of a pressure drop across them to be reasonable
 
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I think the main reason people keep cars for a longer time now is that they can not afford new cars. The price of new cars has gone up a staggering ammount in the last 20 years. The average car is 20-30k now and trucks are even more expensive, and now you need a 10-15 year loan to pay for your car.
I think that has to do with the quality of the used car market as well and like for video car there was a surge (the corolla of today is the camry of yesterday, in size, power, etc.... the new civic is bigger than the 1990 Accord in every way, with 50% more horsepower), because I am not so sure once you feature and inflation adjust that they changed much:

US-CPI-2019-01-New-vehicles-.pngUS-camry-msrp-1990-2020.png

The idea that you need a 10 year's loan instead of being offered an all time low interest financement plan is also a way to see it, you do not need a loan to start with if you are an advanced in age adult (how would you retire one day ?), it is just usually much better financially to take it.

My buddy is a mechanic, and we've both seen numerous vehicles that were either irreparable due to parts not being available, due to cost or they just plainly don't exist. People definitely want their cars fixed and definitely don't want to buy a new vehicle, especially in the past year for obvious reasons.
On a standard/common car (F150, Civic, accord, corolla, etc...) made after 2010, they were irreparable due to parts just plainly not existing ? Must say, would be learning something here.

Yes, cars are used for a longer period of time because people aren't buying newer cars, and especially newer trucks. New vehicles have such terrible reliability issues due to cutting corners and using pencil pushers for car design, rather than properly engineered cars.
I had anything past 2005 has easily newer versus the past in my comment there, those made in 2000s cars are being used way longer than those of the 90s, those of the 90s much longer than those of the 80s and so on. I think price vs quality of the second hand market, a the generation of adult driving significantly less than all the recent one before and other factor are in play to why someone would not buy a new CX-5, Civic or Camry, fear they will be less reliable is probably not there, for not buying the Aluminium F-150, yes in that class of car maybe.

We can go in anecdote, mine will be completely the other way around, in canada cars in the 80s in the morning had issue starting way more than cars now (maybe the quality of oil there and modern battery is removing a lot of this) and all the empirical metric indicate that cars average/median life of usage on the roads has been creeping way up over time, there was an era that 100,000 miles was a lot to reach and you had to change oil every 1,000 miles.

Yes it became much harder to do it yourself all around, but for the average joe modern car seem to be much better than older one, probably why we do not Cuba old car around.
 
Have you never taken an engine apart before? Plastic intake manifolds get just as hot or hotter than a metal manifold because engine coolant often runs through the manifold as it passes between cylinder banks. They often run hotter than metal intakes of the past because modern engines are so choked full of emissions shit, run hotter by design and prevent the escape of heat from the top of the engine like metal intake manifolds of the past.

Plastic and non-metal intake manifolds and other critical components are shit and have no business being on an engine. They warp, crack and literally disintegrate from the extreme heat and cold cycles, often requiring resealing or replacement after just a few years as they start leaking oil or pissing coolant everywhere. This includes leaking on to spark plugs often buried deep inside, causing oil fouling, misfires and dead cylinders.

Plastic intakes are cheaper to produce and cost the consumer more later in headaches and expensive repairs. Basically the car industry in a nutshell, make cheap shitty parts that rapidly fail and don't have replacements available, forcing people to buy new cars after just a few years because no parts are available.

Yes, i do my own car work down to the engine block so long as the job doesn't require some special tool that doesn't make sense to purchase for a one-off. A metal intake transmits the heat it is absorbing from the block and surrounding engine compartment air to the cooler air flowing inside it, that's the only way it can be cooler than a composite intake.

Heat isn't supposed to escape an engine thru the walls of it. That's waste heat. helpful heat an engine produces is put into the exhaust gas. Everything else is waste. Less waste to maintain the designed operating temperature is better. And what do you think is cooling your metal intake manifold? Your intake air ...which then runs hotter and less dense which hurts performance directly.

I'm not sure if you've never worked on an engine or if you're just a trolling "i only work on cars from the 60's and earlier because that's all i understand" car enthusiast. The intake manifold isn't under stress, it exists soley to direct air (and sometimes some fuel in certain cars) to the cylinders ...that's it. They dont expand or contract as much as most metals do because they're not good heat conductors like metals are. And I'm positive that older vehicles with less plastic parts leaked and failed far more frequently than modern vehicles that seem ever increasingly full of these dangerously poor quality / functioning plastic parts.

if they warped and cracked more frequently than their metal counterparts, we wouldn't continue to see the lifespan of vehicles actually being used as daily drivers increase, as well as the average lifespan of engines increasing.
 
I think that has to do with the quality of the used car market as well and like for video car there was a surge (the corolla of today is the camry of yesterday, in size, power, etc.... the new civic is bigger than the 1990 Accord in every way, with 50% more horsepower), because I am not so sure once you feature and inflation adjust that they changed much:

View attachment 313848View attachment 313849
The problem with these "adjusted for inflation" graphs when used as arguments to "prices haven't changed" because 18k sure as fuck isn't 28k. Is that people's take home largely haven't "adjusted for inflation", perhaps the very lowest paid have, and that's only due to minimum wage laws increasing.

That said, I do think there's probably more people who want to get more value out of something, I find very little value in having a "new car" so when I do get a "new car" I make it last for a very long time. Up until the point where maybe maintenance outpaces value.
 
The problem with these "adjusted for inflation" graphs when used as arguments to "prices haven't changed" because 18k sure as fuck isn't 28k. Is that people's take home largely haven't "adjusted for inflation", perhaps the very lowest paid have, and that's only due to minimum wage laws increasing.

That said, I do think there's probably more people who want to get more value out of something, I find very little value in having a "new car" so when I do get a "new car" I make it last for a very long time. Up until the point where maybe maintenance outpaces value.

The problem with inflation is you can't really use it as a good comparison for something where the quality has changed so much. A standard car from 2020 is way different than a standard car from the 90s. A lot of what comes standard in new cars didn't even exist back then. And the measurement for inflation is pretty subjective to begin with.

Bread really hasn't changed but costs 3X as much. The best graphics card now costs more than it did back then, but baby toys now have more advanced computers than you could buy then. And people pay to get rid of tech that old. New AAA games cost the same as they did back then but are wayyyyyy more advanced.
 
The problem with these "adjusted for inflation" graphs when used as arguments to "prices haven't changed" because 18k sure as fuck isn't 28k. Is that people's take home largely haven't "adjusted for inflation", perhaps the very lowest paid have, and that's only due to minimum wage laws increasing.
Source ? I heard debate around if the growth was enough to follow inflation, but they didn't at least largely adjusted for inflation is a first.

1996 median American income household: $35,492
2019 median American income household: $68,703

68,703 / 35,492 = 1.936
27,900 / 17,995 = 1.55

Median household income grew significantly more than that 18k to 28k during that time frame and a 2019 Taurus is a giant sedan (3917 lbs) 288 hp car that is a bit unfair to compare to what would be today a mid sedan 3,3326 lbs 1996 Taurus with a 145 hp (tough and nice Vulcan but still not comparable) engine.
 
A metal intake transmits the heat it is absorbing from the block and surrounding engine compartment air to the cooler air flowing inside it, that's the only way it can be cooler than a composite intake.

Wrong. Vehicles with carburetors and early TBIs spray fuel into the intake, which has a two fold effect in lowering intake temperatures. The first is the fuel is much colder than the engine from being stored away from it, but the bigger effect is from the change of state energy from the fuel going from a liquid to a vapor. More modern vehicles have moved to an injector on valve (EFI), or worse, direct injection (GDI). Fuel only exists right near the valves in EFI and not at all in GDI, plus black plastic is a very good insulator and heat trap. GDI engines are especially terrible in that the valves foul up constantly. Engineers apparently forgot about the natural cleaning power of fuel and quickly went back to a hybrid GDI + EFI setup.

Heat isn't supposed to escape an engine thru the walls of it. That's waste heat. helpful heat an engine produces is put into the exhaust gas. Everything else is waste. Less waste to maintain the designed operating temperature is better. And what do you think is cooling your metal intake manifold? Your intake air ...which then runs hotter and less dense which hurts performance directly.

Engines are always going to produce waste heat, the problem is what to do with it. Of course you can just have a radiator with glycol in it circulating through a water jacket, or you can use other cooling methods in conjunction. Like using a metal intake with coolant running through it, or an oil cooler, or both.

I'm not sure if you've never worked on an engine or if you're just a trolling "i only work on cars from the 60's and earlier because that's all i understand" car enthusiast. The intake manifold isn't under stress, it exists soley to direct air (and sometimes some fuel in certain cars) to the cylinders ...that's it.

Pretty clear you have next to no experience with automotive technology. Air is not the only thing that flows through an intake manifold. Air, fuel, coolant and even EGR can flow through an intake manifold. Here's one example of thousands:

Remember that part I said about manifolds warping and cracking? I've worked on all vintages of cars from the 60s to present day, it looks like you work on maybe one or two?

They dont expand or contract as much as most metals do because they're not good heat conductors like metals are. And I'm positive that older vehicles with less plastic parts leaked and failed far more frequently than modern vehicles that seem ever increasingly full of these dangerously poor quality / functioning plastic parts.

My 33 year old truck with 260,000+ miles on it is more reliable than my dad's 2017 Ford Focus. Older cars leak and fail because people don't take care of them. Gasket technology is another thing that has changed over the years. Modern multi layer graphite and metal and moulded vulcanized rubber on metal frame gaskets are way better than the cork and asbestos gaskets that used to be common.

if they warped and cracked more frequently than their metal counterparts, we wouldn't continue to see the lifespan of vehicles actually being used as daily drivers increase, as well as the average lifespan of engines increasing.

I definitely don't see modern engines as more reliable. I see them getting ever smaller with ever bigger turbos or supers with other complex electronics that increase failure rates. Modern engines are so reliant on software control and an eye watering number of expensive sensors that it makes them far less reliable. Coupled with other dumb shit like removing oil and transmission dipsticks and telling car buyers that they have "lifetime" transmission fluid. Yeah, lifetime of the fluid until it burns and detonates the transmission so they can sell you another car.
 
Have you never taken an engine apart before? Plastic intake manifolds get just as hot or hotter than a metal manifold because engine coolant often runs through the manifold as it passes between cylinder banks. They often run hotter than metal intakes of the past because modern engines are so choked full of emissions shit, run hotter by design and prevent the escape of heat from the top of the engine like metal intake manifolds of the past.

Plastic and non-metal intake manifolds and other critical components are shit and have no business being on an engine. They warp, crack and literally disintegrate from the extreme heat and cold cycles, often requiring resealing or replacement after just a few years as they start leaking oil or pissing coolant everywhere. This includes leaking on to spark plugs often buried deep inside, causing oil fouling, misfires and dead cylinders.

Plastic intakes are cheaper to produce and cost the consumer more later in headaches and expensive repairs. Basically the car industry in a nutshell, make cheap shitty parts that rapidly fail and don't have replacements available, forcing people to buy new cars after just a few years because no parts are available.
The first years they used plastic intake manifolds, they were inadequately engineered. That is no longer true.

Written by a mechanic: https://www.carid.com/articles/why-does-my-car-have-a-plastic-intake-manifold.html

More and more automakers are switching to plastic intake manifolds. After decades of testing and studying common failure points, optimum blends of plastic with 35% fiberglass or related glass elements have been perfected to enhance both strength and elasticity. Today's plastic intake manifolds are more than just mere plastic.

Greater strength from engineered compounds resists cracks under pressure where it's most needed, and greater elasticity yields the ability to stretch and snap back - preventing permanent warpage which causes leaks. Failure rates of quality plastic intake manifolds manufactured in recent years have dropped significantly, and high reliability over long-term use makes them a smart purchase.

Thicker construction in critical areas prevents erosion from dirty coolant, and the addition of aluminum reinforcements provides increased load-bearing capacity for external fittings and components. Plastic compounds dissipate heat better than metal, so air flowing through intake tubes remains cooler to aid combustion.

Sound-deadening acoustic qualities of newer compounds have been improved, making them as good as their metal counterparts in eliminating raucous and unwanted engine noises. Silicone-based gaskets allow better flex between dissimilar materials, and they help eliminate corrosion and vibrations. more details on - https://www.carid.com/articles/why-does-my-car-have-a-plastic-intake-manifold.html
 
The first years they used plastic intake manifolds, they were inadequately engineered. That is no longer true.

Fiberglass impregnated plastic does give it a better tensile strength, but it does nothing to help with the heat and corrosive coolant. If you pause the video I linked above at 2:44, the break shows the fiberglass inside the plastic. When regular plastic without fiberglass cracks or shatters, the area of the break often looks like shattered obsidian and can be razor sharp. Broken fiberglass impregnated plastic looks like asbestos on the surface where the break occurred.

Ford 4.6 and 5.4L intakes are a really stupid design. Instead of having a two piece intake where the plastic is only used for air inlet, and aluminum for the coolant, they make the coolant go through two rubber seals and a plastic spacer.
 
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