Which metal is considered the most durable? Stainless steel, ceramic or titanium

Titanium or steel?

A very popular question that torments many: “Which valves to buy: steel or titanium.” In this article we will try to help you make your choice.

What are the differences between titanium and steel valves, and why is there no overall winner?

Valve weight.

Titanium motocross valve (14 grams)

The first difference that catches your eye is the weight of the valve. A titanium valve with the same dimensions is much lighter than its steel brother. The spring will close the valve faster, the mass of which is less, therefore, the less the weight of the valve, the higher the maximum speed bar can be raised with less risk of the piston catching up with the valve. At the same time, the load on the timing belt as a whole is reduced, this gives some increase in power due to a small increasing efficiency. For example: Almost all modern motocross and circuit racing motorcycles use titanium valves.

Steel valves with the same size have more weight, so stiffer springs are used with them. If the spring stiffness is insufficient, the likelihood of the valves being hit by the piston increases when the engine operates at high speeds. The stiffness of the springs and the greater weight of the valves create an increased load on the timing belt. Even on small engines of motocross motorcycles with a volume of 125 cc. With steel valves, fairly stiff and even double springs are used.

Wear resistance.

Titanium alloys are far inferior to steel when it comes to wear resistance. The poor antifriction properties of titanium are due to the adhesion of titanium to many materials and its interaction with nitrogen and hydrogen during high temperatures, because of which upper layer becomes brittle and crumbles during use.

Multi-layer protective coating of titanium valve disc developed in our workshop

To improve anti-friction properties, increase wear resistance and protect against external environment titanium valves are covered with protective coatings various types. The thickness of such coatings, depending on the type, varies from several thousandths to hundredths of a millimeter. This makes it impossible to grind the valve to the seat in order to seal the combustion chamber, because During lapping, the protective coating will inevitably be damaged, and the valve will quickly “fall” into the seat. Therefore, when installing titanium valves, increased demands are placed on the shape, cleanliness of the chamfers on the seats and their alignment with respect to the guide sleeve.

The wear resistance and anti-friction properties of steel are an order of magnitude higher than those of titanium, but significantly lower than those of the protective coatings that cover the titanium valve. At the same time, the wear resistance of the steel valve chamfer is maintained throughout the entire thickness of the plate, and the titanium valve chamfer retains its properties and parameters exactly as long as the protective coating lasts.

Thermal conductivity, expansion coefficient and thermal gap

The thermal conductivity and resistance to high temperatures of titanium alloys is lower than that of heat-resistant steels. Valve plate cooling plays an even more important role important role when using titanium valves. This is why it is recommended to use bronze valve seats with titanium valves, which better conduct heat away from the hot valve plate.

The expansion coefficient of titanium is much less than that of steel. When using titanium valves, a smaller thermal gap between the guide and valve is allowed than when using steel valves. This has a positive effect on the accuracy of the valve seating, which increases the service life of the seat-valve pair.

Valve and repair cost

On average, titanium valves are more expensive than steel valves. Firstly, because titanium is much more expensive to produce than steel. Secondly, the production of titanium valves requires additional production steps (coating). And finally - marketing.

Although sometimes you can find steel valves whose cost is comparable to titanium ones. More often, this picture is observed with original spare parts, where the main percentage of the cost is occupied by marketing.

If the chamfer is damaged, restoring a steel valve will cost 3-4 times less than a titanium valve.

Resource

"Breakage" of the titanium valve of the Yamaha Phazer 500 and "breakage" of the steel valve of the KTM EXC 450

Due to the thin protective coating Titanium valves are indeed more capricious than steel ones, especially if they are neglected and not properly maintained. But, from experience, both steel and titanium valves, with proper attention and maintenance, last equally long.

During our work, we had to see “dead” valves at low mileage, both on steel and titanium sets.

It makes sense to replace steel valves with titanium in cases where:

The engine is regularly operated at high speeds

It is planned to modernize the engine to increase power

Regular high-quality maintenance of equipment is carried out

There is a change in the purpose of the equipment (from enduro to cross, for example)

It makes sense to replace titanium valves with steel If:

The engine is not operated at high speeds

Difficulties with maintenance (carrying out independent maintenance and repairs)

There is no possibility to process the seats (it is possible to lap the valves)

Titanium analogue is too expensive

Always use only springs that are designed for of this type valves!

When using new valves, we strongly recommend that the seats be machined (chamfered) good equipment. This is especially important when using titanium valves. Lapping of titanium valves is not permitted.

The making of armor begins not from the moment when the craftsman begins to bend plates or rivet rings, but from the choice of metal. To be precise - from its production. Neither in the old days, when blacksmiths were just learning to produce the armor that interests us so much today, nor now can we do without steel. On modern market There are several common options, which we will consider.

So, let's say we don't have screaming iron, a real forge, and the ability to smelt metal from ore ourselves. Let’s say without exaggeration, everyone finds themselves in this situation. And, although everyone solves this problem in their own way, their choice of materials is not so wide.

These materials are quite easy to list - which is what we will do. St3 steel is the most typical and simplest thing you can use to make your complex. It differs from the steel that blacksmiths had at their disposal in the old days, at least in that this steel is factory-made, and its composition, of course, is standard, no matter where you purchase it. These are usually sheets about a millimeter thick. If the steel is thicker, the armor will be too heavy; if it is thinner, it will not be strong enough. Modern steel is stronger than medieval steel, it can be knocked out quite easily, given any shape, and the result is good armor - of course, if the material is in your hands experienced craftsman. This steel is of higher quality than what was once available to craftsmen, but overall it is quite suitable for creating armor. It is more durable, processed differently, but is the closest thing to authentic material readily available on the market.

The average weight of a set of armor made of St3 steel is 20-25 kilograms, sometimes it can reach up to 30. Of course, you can only move easily in them if you have skill, but anyone who has trained more or less regularly knows how this skill is achieved. In addition to this common grade of steel, there are other options. For example, titanium was completely unknown in the Middle Ages, but modern reenactors make armor from it, and quite successfully. Of course, we are not talking about titanium in its pure form, but about a complex alloy with titanium. Titanium alloy is more carbonaceous than steel, it is stronger and lighter, does not wrinkle from impacts and is easier to process, so armor can be made from it faster. The strength of the alloy is such that it can be used to make plates less than a millimeter thick - approximately 0.8. The smaller thickness entails significantly less weight, which the fighter will carry on his shoulders when he enters the lists. Thus, a “titanium” complex weighs on average about 15 kilograms, and the heaviest one weighs up to 20, lower limit for normal armor. For example, plate gauntlets, due to the use of this alloy, lose about 30 percent of their normal weight; body protection of the same model can weigh 12 kilograms instead of 20.

Finally, armor is often made from stainless steel, an alloy that does not corrode. In general, the characteristics of such armor will be the same as those of armor from ST3, but the owner will be spared the need to constantly clean armor rusted from dew or rain. Thus, “stainless” armor is easier to maintain, but its historicity is questioned by some due to the fact that real authentic armor simply has to rust. Modern rules do not prohibit the use of stainless steels in the manufacture of sets of protective equipment, but the correctness of their use from the point of view of historical reconstruction of the Middle Ages remains a controversial issue.

From choice kitchen knife Not only the convenience of cooking depends, but also the preservation of vitamins. For example, a sawtooth knife is good for bread; it can be used to cut without damaging the crumb.

In order for a piece of metal to become a knife, it must first be deformed, after which the workpiece is sent to the furnace. After forging and heat treatment, the geometric parameters of the future knife are set, that is, the blade itself is formed, then the handle is made.

Is the knife ready to become useful assistant in the kitchen depends on many factors, the main thing is the geometry of the blade and the thickness of its cutting edge - the thinner it is, the better. In order to check the geometric parameters of a kitchen knife, you need to take the base of the butt and move two fingers in a sliding motion towards the cutting edge; if you do not feel any difference, then the knife is made with high quality.

The main parameter when choosing a knife is the thickness of the cutting edge.

In contact with water and food, stainless steel oxidizes. This is why foods sometimes have a metallic taste.

Stainless steel does not resist corrosion as flawlessly as many people think. Tiny lesions eventually coat the surface of the knife and penetrate the steel.

But ceramic knives are resistant to chemical attack and biologically inert, which is very important when cutting greens or vegetables. But such a knife has a significant disadvantage - when cutting frozen meat, a chip may occur on the cutting edge of the knife.

Titanium knives are also completely food neutral, but other than that, they do not deteriorate when cutting hard foods. At correct use Such knives remain sharp for several years.

Every vegetable and fruit contains special enzymes specific for each vitamin. While they are in the whole fruit, the oxidation process does not occur, but as soon as we start cutting, for example, an apple, we release the cell juice out and immediately these enzymes begin their destructive process. To preserve the vitamins contained in foods as much as possible, cut them into large pieces.

All knives that are susceptible to corrosion also initiate the above process. If we divide knives according to the degree of usefulness, then the first place will be taken by a ceramic knife, the second by titanium and the third by stainless steel. Well, if you take everything into account consumer properties knives, in particular their mechanical strength, That titanium will come first, but it is much more expensive.

From childhood we know that the most durable metal- this is steel. We associate everything iron with it.

Iron Man, The Iron Lady, steel character. When we pronounce these phrases, we mean incredible strength, strength, hardness.

For a long time, steel was the main material in production and armament. But steel is not metal. More precisely, it is not entirely pure metal. This is with carbon, in which other metal additives are present. By using additives, e.g. change its properties. After this, it is processed. Steelmaking is a whole science.

The strongest metal is obtained by introducing appropriate alloys into steel. This could be chromium, which imparts heat resistance, nickel, which makes the steel hard and elastic, etc.

In some areas, steel has begun to replace aluminum. Time passed, speeds increased. Aluminum couldn't stand it either. I had to turn to titanium.

Yes, yes, titanium is the strongest metal. To give steel high strength characteristics, titanium began to be added to it.

It was discovered in the 18th century. Due to its fragility, it was impossible to use. Over time, having obtained pure titanium, engineers and designers became interested in its high specific strength, low density, resistance to corrosion and high temperatures. Its physical strength exceeds the strength of iron several times.

Engineers began adding titanium to steel. The result is the most durable metal, which has found application in ultra-high temperature environments. At that time, no other alloy could withstand them.

If you imagine an airplane flying three times faster than you can imagine how the covering metal heats up. Sheet metal The skin of the aircraft in such conditions heats up to +3000C.

Today, titanium is used unlimitedly in all areas of production. These are medicine, aircraft manufacturing, ship production.

It is clear that titanium will have to move in the near future.

Scientists from the USA, in the laboratories of the University of Texas in Austin, discovered the thinnest and most durable material on Earth. They called it graphene.

Imagine a plate whose thickness is equal to the thickness of one atom. But such a plate is stronger than diamond and transmits a hundred times better electricity than computer chips made of silicon.

Graphene is a material with damaging properties. It will soon leave the laboratory and rightfully take its place among the most durable materials in the Universe.

It is even impossible to imagine that a few grams of graphene would be enough to cover a football field. This is metal. Pipes made of such material can be laid manually without the use of lifting and transport mechanisms.

Graphene, like diamond, is the purest carbon. Its flexibility is amazing. This material bends easily, folds perfectly and rolls perfectly.

Manufacturers of touch screens have already begun to take a closer look at it, solar panels, cell phones, and finally, super-fast computer chips.

Today, watches serve as an indispensable accessory for everyone. modern man, with the help of which you can advantageously emphasize your high status, as well as stand out from the gray mass. Therefore, it is very important to approach the choice the best option. Watches made of titanium and steel are especially popular due to their excellent performance characteristics.

Steel watch

Stainless steel watches are the most common. Mass and relatively inexpensive production of this material allows us to offer watches in a wide price range. The inertness of steel protects the case and parts of the watch mechanism from oxidation and “aging”. Steel is characterized by increased viscosity, which makes it resistant to external damage: upon impact, steel watches do not split or crack. There are quite a few formulas of steel alloys; the best steel in terms of strength, used for the manufacture of watch cases, is low-carbon 316L.

Advantages:

• impact resistance;
• ease of use;
• ratio of quality and price;
• wear resistance;
• If scratches occur, it can be easily restored appearance using polishing.

Flaws:

• heavy weight.

Titanium watch

Titanium in watchmaking

The complexity of the process of mining and processing titanium ore. The production of rough blanks is expensive - the technology involves melting titanium at high temperatures and casting in a vacuum. The complexity of mechanical processing of the product, due to high strength titanium. All this significantly affects the cost of the final product, and until the end of the 20th century, the use of titanium in watchmaking was considered unprofitable.

But as has happened more than once, the military set the pace. At the end of the 80s of the last century, for the troops of the German Bundeswehr, IWC produced a watch in a titanium case - the Ocean Bund.

These models are still in great demand among collectors, especially the “Diver – Sapper” version (German: Minentaucher). They were developed for underwater miners, therefore, along with the requirements for accuracy, shock resistance, water resistance, it was assumed that the watch should be lightweight, resistant to sea ​​water, not susceptible to the influence of magnetic fields. Titanium met these requirements perfectly. It is worth noting that back in 1978, thanks to the IWC brand, the titanium Porsche Design Compass Watch appeared, created together with the grandson of the famous Porsche, designer Ferdinand Alexander. Started in 1982

The first production titanium watch Ocean 2000 from IWC was produced. They were intended for divers, had a water resistance of 2000 meters and were also developed together with Porsche.

Subsequently, titanium firmly established itself as one of the materials for the manufacture of watch cases and bracelets, and began to be used by many manufacturers. Titanium is also popular in the watch industry because it does not cause allergies at all.

Due to low thermal conductivity (13 times lower than the thermal conductivity of aluminum), titanium watches are warm and do not cause discomfort to the owner even in the cold season. At first, only some parts of the watch mechanism were made from titanium alloys, later – bracelets and the case. Such alloys are characterized by absolute inertness, i.e. they do not interact with other substances, do not rust or change color. Moreover, titanium alloys do not react to magnetic influences, which provides the more precise movement required for professional chronographs. Titanium is also considered the safest metal; alloys with it, unlike stainless steel, do not cause allergic reactions.

Advantages:

• in alloys, titanium is 5 times stronger than steel;
• withstands pressure of 1000 MPa;
• light weight;
• 100% corrosion resistance;
• scratches are less noticeable on titanium, although they appear more easily than on steel;
• hypoallergenic;
• more accurate move.

Flaws:

• plastic;
• high price;
• the danger of the lid “merging” with the body due to the tendency to diffusion, that is, the lid must be opened periodically;
• difficult care.

Titanium connections and watches

When considering titanium in watchmaking, it is worth mentioning the compounds - titanium carbide and titanium nitride.

Titanium carbide is used as a coating for watches. This coating has a noble black color and is quite resistant to abrasion. Nitride coating is similar in color to gold. Can be used independently, and as an intermediate layer between the base of the case and the gold plating applied to it. This reduces the cost of production, due to the fact that such a coating is cheaper than gold. When the top layer is abraded, the flaw on the body is less noticeable. If n.titanium is applied to a brass body (the metal is relatively soft), this additionally makes the coating more wear-resistant.

Comparison of materials

Titanium watches are an indispensable device for all lovers of an active lifestyle, as they specifications allow their use in the most unfavorable environments. Their main quality can be called exceptional strength. Titanium alloy is quite plastic in its structure, which allows you not to be afraid of excessive damage associated with with strong blows housing on a hard surface.

Titanium, unlike steel, initially has hypoallergenic properties and does not require any measures to prevent the surface of the watch from coming into contact with the skin.

Another property of titanium is low thermal conductivity. In practice, this means that, having warmed up from the hand over time, a titanium wrist watch will maintain a temperature that is comfortable for a person. And this despite any temperature changes outside. You can buy a titanium watch and not worry about your feelings either in summer or in winter while traveling to the most exotic places. They won't let you down.

And finally, another important property of titanium watches is lightness. Titanium watches often look almost like steel watches. But at the same time their weight differs by an order of magnitude. With long-term use, this can be an important and very convenient quality.

Is it worth overpaying for titanium? The advantages of titanium are that it is lighter than steel, does not have an allergic effect and, indeed, scratches are less noticeable on it (with the exception of polished surfaces). And the decision is up to you! 😀

Graph

I'm looking for a watch now. Sometimes there are models with the same mechanisms and design, but one is in steel, and the other is titanium. The latter is usually 20 percent more expensive. I'm wondering if it's worth overpaying for titanium? Ordinary titanium scratches easily (easier than ordinary steel). Therefore, all sorts of clever coatings are often used for titanium, which, however, can completely wear off over time. In general, when I hold a titanium watch in my hand, it feels like the watch is made of plastic.

Anonymous

Looking at your steel watch, it will be quite difficult to squeeze out that steel scratches the least - in the sense that it is difficult to call it less... more precisely, everything else scratches even more.

Both titanium and steel watches that passed through my hands were scratched approximately equally, but I decided for myself a long time ago - no surfaces polished to a shine in watches for every day and for leisure. only matte. In fact, “matte” (at least the standard) scratches even better than

"polishedness". By the way, some knives are coated with stonewash, specifically “scratching” them in such a way that later other scratches are not particularly noticeable.

Maria

Approximately the same price niche as steel watches is occupied by watches with titanium cases. This metal is called “winged” because it is actively used in aviation and rocketry due to its low weight and high strength. Titanium itself is quite fragile, and titanium alloys, which are more ductile, are used to make watches. Titanium, like steel, does not require coatings, it is hypoallergenic and does not cause skin diseases. Titanium watches have two advantages over steel ones: they are very light and “warm” to the touch. The latter sensation arises due to the fact that titanium has low thermal conductivity. Most titanium watches have a specific matte gray color, but some manufacturers make cases from polished titanium, and then the result is interesting combination: The watch looks like steel, but weighs almost nothing. Perhaps the only drawback of titanium watches is that they easily develop small surface scratches. In addition to low weight and low thermal conductivity, titanium also has another interesting property: If you squeeze two pieces of titanium together, they can “weld”. Therefore, watches with a titanium case and a titanium back cover must be opened occasionally, otherwise the cover may “grow” to the case.

conclusions

Steel watch

Steel watches are especially popular and in demand through affordable price. This can be explained by the low cost of the material, as well as the equipment for watch production. Therefore, there is a wide range of products on the market various options steel watches, which are a budget option.

Among the advantages of steel watches are:

• Resistance to mechanical stress.
• Simplicity and ease of operation.
• Low price matches good quality hours.
• Long service life.
• By polishing you can easily restore minor imperfections on a metal case.

In addition to the advantages, steel watches also have disadvantages, among which are:

• Heavy weight.
• A budget version of a watch that is not capable of emphasizing its high status in society.

Titanium watch

Titanium is used in many industrial areas due to its excellent performance characteristics. Today, men's wristwatches are also made from this durable and reliable material.

Among the advantages of titanium watches are:

• First of all, it is worth highlighting the provision of accurate watch movement through the unique ability of titanium to respond to a magnetic field.
• In addition, titanium is considered environmentally friendly and safe for the human body. The material does not cause allergic reactions or other skin irritations.
• It is also worth highlighting the incredible strength of titanium. This allows you to create shock-resistant watches that are not afraid of mechanical impact.
• In addition, titanium also withstands high pressure and is characterized by low weight compared to steel.
• Titanium also has excellent resistance to negative impact environmental factors. In other words, the case of such watches is not afraid of moisture. The high price of titanium watches and the need for special care is the main disadvantage of titanium watches.