Questions tagged [metals]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
9
votes
2answers
151 views

Material selection for weight scale

I am looking to test the FlexiForce sensor in measure force, however for accurate readings the load needs to be disturbed evenly over the sensing area. As such I am having "discs" made to cover the ...
8
votes
4answers
3k views

Do “non-iron steels” exist?

There are numerous steel alloys, containing mostly iron, carbon, and some other metals. Generally speaking, we can think of them as if they were some type of steel. My question is: do "non-ferrous ...
8
votes
1answer
254 views

Weldability of Pure Tin

The site states that Tin cannot be welded, but after I made some research, I discovered that tin, when alloyed with copper or used as a protective coating for steel, can be welded. My question is why ...
7
votes
2answers
946 views

Is this railway carriage side likely made of single metal sheet?

A neat image from Wikipedia: Here the railway carriage side looks like it is crafted from a single sheet of metal (if we ignore the doors and the windows and some minor parts like that small thing ...
7
votes
2answers
1k views

Metal micro perforation

I'm trying to design a metal surface with micro-perforation for a product and light it from other side with LED, such that the perforated pattern appears only when lit. In my previous prototype, ...
6
votes
2answers
5k views

How metal fittings seal connection without rubber gaskets?

I am well familiar with the concept of gasket. From my non-mechanical engineer perspective, I can understand how a standard rubber gasket works in various plumbing ...
6
votes
2answers
724 views

How can I finish a round hole so it has 90 degree corners (flat bottom)?

I have a 10 mm depth x 5 cm length 99% Tungsten rod. How can I machine the described hole so that instead of having a bevel from the tip of the main drill-hole bit, it has a perfect 90 degree corner ...
6
votes
1answer
923 views

What are typical forging loads?

What are typical forging loads for various metals and configurations? I know that the typical test for a metal is to upset a 0.750" high x 0.500" diameter cylinder to a height of 0.5", but could not ...
5
votes
2answers
2k views

Metal spring thermal expansion

I am attempting to figure out why a laser layout tool I have is drifting over time. It was designed with a small adjustment mechanism that relies on a spring to apply pressure to a fulcrum that ...
5
votes
1answer
143 views

Optimal size and shape for a steel target?

Problem I'm building a steel target for long-range rifle shooting. For those unfamiliar, the purpose of the steel is to produce a loud "PING" when the bullet strikes the target. It's very fun. Since ...
4
votes
1answer
133 views

Purpose and name of fine pitch marks on a cast metal part

I have seen this kind of mark on various cast metal parts. This is an image of the base casting of a hard disk drive made by HGST. What are these marks for? What are they called?
4
votes
1answer
3k views

Strongest brazing materials for titanium?

What are the strongest brazing materials for titanium? The main materials I would like to use would be copper or silver, in which case I would like to ask which would form a stronger bond with ...
4
votes
1answer
189 views

How small can you get a stream of molten steel to be at low pressure?

I'm designing a crucible / extruder, and right now it has a .6mm hole to extrude from. Will this work? A chart with various metals listed would be nice. Pictures: Click to expand
4
votes
2answers
89 views

Frequency dependence of electromagnetic shield metal

I know that the effectiveness of metals used for electromagnetic shields heavily depends on the used frequency or frequency range. I could not find a resource in the web (tables or graphs) that give ...
4
votes
2answers
156 views

What grade of titanium are “memory titanium” glasses made of?

I've worked with different grades of titanium. Mostly with grade 5, and also grade 1 which is ductile. I know that some glasses are made of titanium and are called "memory titanium", I guess because ...
4
votes
1answer
173 views

How to calculate the bending resistance of a square metal bar?

I have an old bend/twisted wooden door. It has some character to it so I want to keep it and add square metal bars to straighten it. I have provided a sample drawing of the door and where it is ...
3
votes
5answers
425 views

What would be a practical way for removing thousands of padlocks from valuable bridge railings?

Inspired by this story about Paris authorities ordering removal of thousands of "love lock" padlocks from bridge railings. This is not a DIY SE question because it's not DIY scale in the first place. ...
3
votes
2answers
4k views

Difference between Precipitation Hardening and Tempered Martensite

The textbook "Materials Science and Engineering An Introduction" mentions that: "Precipitation hardening and the treating of steel to form tempered martensite are totally different phenomena, even ...
3
votes
1answer
1k views

Is it necessary to preheat an investment casting mould when working in a vacuum?

Normally, in investment casting, the mould is preheated before pouring the liquid metal in to reduce thermal shock from rapid cooling. In a vacuum, the heat transfer due to gas convection is reduced ...
3
votes
1answer
694 views

How do I use this “ Low-Density, High-Hardness, High-entropy Alloy” to make a good shortsword?

Given the information on swords here: When you need to place a great deal of strength into a thin blade, steel remains the best all around choice. Titanium blades will be simultaneously weaker and ...
3
votes
1answer
161 views

Would a T-800 with a gold skeleton deform under stress?

Over in Programmers chat we were discussing whether a gold skeleton would be feasible. That got me thinking: If I were to build a Terminator (T-800) using pure gold as the endoskeleton, would the ...
3
votes
1answer
352 views

How thick does an aluminium vacuum cylinder have to be?

Take a hollow aluminium cylinder with outer radius $r$ and length $h$, capped with two circular endcaps. How thick does the aluminium have to be, that is what is the inner diameter of the cylinder, ...
3
votes
1answer
37 views

Can chemical vapor deposition chambers be used to lay down thick layers of metal?

Can CVD Chambers be used to lay down thick (~1 mm) layers of metal?
2
votes
2answers
191 views

Why did the Soviet Alfa-class submarines have a titanium hull?

My limited knowledge in engineering tells me: Titanium is expensive, stronger and heavier than aluminium, lighter and weaker than high yield steel. The most significant advantage of titanium is the ...
2
votes
2answers
115 views

Is there a drill adaptor or attachment tool for cut a metal solid cylinder

I need to cut a 7mm solid Aluminium plug (Non-hollow and non-threaded) to replace a part in my car. Is there a simple drill adapter tool to cut a solid metal cylinder (Plug) from an Aluminium mass ? ...
2
votes
2answers
2k views

What's the difference between tempering and aging?

The processes sound really similar; I'm asking with respect to Martensite processing. Essentially the difference between Tempered martensite and Aged martensite for Steels
2
votes
2answers
157 views

Which materials can be used to make permanent casting molds for cast iron?

I am interested in comparing the different materials that can be used to make castings of cast irons, and therefore was wondering which material is commonly used/which materials can be used to make ...
2
votes
2answers
103 views

Heating Sand/Ceramic/Refractory Material under vacuum

In a Vacuum Metallurgy (Casting), a mold needs to be heated (500 to 700 degrees) to reduce thermal shock on the metal surface. Normally, a gas fired oven is employed for such job, but in a vacuum ...
2
votes
2answers
2k views

Is a metal Prince Rupert's drop possible?

Can a Prince Rupert's drop be made of metal instead of glass?
2
votes
1answer
197 views

What is the ideal metal sheet thickness used in a 1 tonne atv/tractor dump trailer?

What would the ideal thickness of the dump trailer bed be, so it can withstand loading rock from a height of 1 meter? The spacing of ribs is yet to be decided. The goal is that the trailer be as ...
2
votes
1answer
69 views

What mechanism is available to rotate a metal piece on another metal piece?

I am trying to find some type of mechanism where I can have a smooth but not too stiff rotation between two metal pieces. I was thinking of putting a shoulder screw through the pieces (the pieces will ...
2
votes
2answers
108 views

38CrNiMoAlA: Does it even exist?

I have some plungers made of 38CrNiMoAlA. Their required hardness to be achieved via quenching/tempering is 51 HRC. I've scoured our technical order for heat treatment of steel alloys but the material ...
2
votes
3answers
63 views

Support columns inside metal tubing

Does structural metal tubing (e.g., either as HSS, or in space frames, or even motorcycle/bicycle frames) ever come with any small metal rods or columns inside of the tubing itself? While it might ...
2
votes
1answer
2k views

Sheet Metal Bending: stuck on calculating the minimum radius required

I'm used to calculate the minimum radius required for bending operations on both aluminum and steel sheets, given the following parameters: https://imgur.com/a/7akHC Problem statement: For a sheet ...
2
votes
1answer
63 views

Coating gold on to sunglasses lenses?

Recently I have been trying to find out more about the process that is used to coat glasses lenses with gold. I asked about it in another forum last night and I was directed here. I initially thought ...
2
votes
1answer
69 views

What paint/spray on material should I use to insulate a metal pole?

I am not entirely sure if this is the correct forum to ask this question so please refer me on if there is a better arena. I am creating a small weather station and I wish to measure soil ...
2
votes
2answers
1k views

Heat treatment processes for ferrous metals

I am trying to find out information about the heat treatment processes of ferrous metals as part of a project which involves making a screwdriver. This includes: Hardening, Annealing, Tempering, ...
2
votes
1answer
447 views

How to use sample holder on Metallography specimen preparation machine Struers Tegrapol-21

In lab we have Struers Tegrapol-21 grinding and polishing machine. I use it for sample preparation. Usually I put 6 samples at once and prepare them with sample holder. However today I need to prepare ...
1
vote
1answer
5k views

Galvanized Steel (Zinc Plated Steel) vs Stainless Steel

Zinc Plating is known for its ability to prevent most corrosion, and it is done by just dipping a metal in hot pool of zinc and letting it cooldown. Meanwhile, stainless steel, an alloy that is ...
1
vote
6answers
795 views

How to create an airtight connection between Stainless Steel and PTFE?

I have these two parts shown below, the bottom cylindrical part is stainless steel, the rectangular upper piece is PTFE (Teflon). The SS prongs from the lower part need to insert into the holes of the ...
1
vote
1answer
180 views

With which parameter can you specify whether a metal is ductile or brittle

I have to do a durability approval of feather key (shaft-hub connection) and the formulas are dependent if the shaft respectively the hub is ductile or brittle. But what is the decision about to say ...
1
vote
2answers
1k views

Pouring aluminum into another block of Aluminum

I have a 120mmx120mm brushless fan with an Aluminum frame, which as you can imagine, isn't very thick. I want to thread the base, so I can mount it with a fairly large screw. For that I need to add ...
1
vote
1answer
16 views

How can we tell if a press mold need more stages?

I was asked to design a simple press mold for a 0.5mm sheet metal part. It has some small but rather deep sinks (5-7mm) which has made me wondering if it can be done in a single stage or it needs more ...
1
vote
2answers
57 views

How were these candlesticks made in the 1800s?

"Candlesticks" for this question are really just a stand-in for axisymmetric silver, brass, etc structures, possibly hollow and made of thin sheet material? Examples: From my research, today we ...
1
vote
1answer
99 views

No increase in temperature during bending?

Good day, I am a mechanical engineering student, we conducted three-point bending test for a metal specimen and I am wondering why the temperature of the specimen did not increase as the UTM certainly ...
1
vote
1answer
178 views

Design a composite material with good wear resistance and electrical conductivity

For a electrical switching device which opens and closes frequently and forcefully. Would a combination of a soft polymer matrix and a conductive metal fibre be a good choice for this? While polymer ...
1
vote
1answer
32 views

Bendable flaps on sheet metal

I'm trying to cut some bendable flaps on aluminium sheets for hooking/clipping onto some fabric. The flaps I have in mind look like this: Are these common features? Does anyone know the geometry of ...
1
vote
2answers
47 views

Best way to dent a pipe from the inside?

I am currently trying to redesign a pipe with 2 dents from the inside. What is the best way to manufacture something like this, also how would i go about describing this process in a drawing? In the ...
1
vote
3answers
181 views

How to increase maximum rotational speed limit of a reduction gearbox?

Reduction gearboxes made of machine steel gear have a maximum limit to prevent changing their physical properties (softening). They change their properties as a result of the temperature increase ...
1
vote
1answer
1k views

Hand-pressed metal stamping - fishing spinner blades [closed]

I want to stamp my own fishing spinner blades. They look like this: http://lurepartsonline.com/Online-Store/Colorado-Blades/Premium-Finish-Colorado-Blades.html Specs are usually 1mm thick, 3x2" ...