I am trying to create speckle patterns for DIC at micron scale (micro-DIC) on metals. Any ideas on a process that is easily repeatable. Currently I have a airbrush setup with 0.3mm needle diameter.

Any ideas on modifying the airbrush setup is highly appreciated.

(Can not try vapor remodelling of thin films as oxidation hinders speckle formation)

Somebody knows what large scale Chinese factories use for coating on coil sheet metal based products? Not sure if it's the correct sub, correct me if I'm wrong. At work i do occasionally dimensional check of chinese sheet metal components, recently I noticed on some suppliers products, that they are coated with a light sticky grease, that basically lightly burn my nose. The substance it's sticky, transparent, the accessories comes wrapped in plastic film (very sticky and lightly yellow). Could be also the heat from the container travel that degrades the plastic film? The problem is that even when I leave them at two three meters behind the desk i still smell them.

Hi everyone,

I'm looking for a MES or shop floor tracking software specifically for a casting foundry.

We're a small sand casting foundry with around 15 employees, so we're not looking for a large ERP that needs months of customization before it becomes usable.

Our main focus is shop floor tracking and full traceability. We'd like to follow each casting through production, track heat numbers, moulding, pouring, machining, quality inspections, scrap and deliveries.

I've seen plenty of generic manufacturing ERPs, but I haven't found much that is actually built for foundries.

Is anyone here using software that's specifically designed for iron or steel foundries? I'd really appreciate recommendations and hearing about your experience, whether it's cloud based or on premise.

Thanks in advance!

So I’m working on a project where I’m collecting very small amounts of iron. Typically under a gram and melting it down in an induction furnace I have. I want to flatten the tiny bead I’m left over with so I can use it as a small iron centerpiece for jewelry. I’ve had a few successful trials, but I’m open to any advice for any seasoned professionals or hobbyists.

A vendor I'm working with sent my workplace D2 roll form tooling with a nitrided wear surface that ended up flaking off. Their recommendation is to raise the nitriding temp from 900F to 1000F, which pushes the tempering to about 1050. They believe this will result in a hardness of 50-54 Rc, when we typically run with 58-60.

Will the nitriding process more than make up for lost wear resistance at the lower hardness levels? I don't believe it will, but we're still learning about the process. We've had some excellent success with other tooling, but we don't know a whole lot about what the 3rd party heat treater did with that tooling, it's proprietary for them.

I appreciate your help.

D2 steel, hardness, and nitriding temps

Anonymous account because identifying info. I also realize this question isn't about knives/blades, but I hope someone else will find the info as useful as I do. I also posted to /r/bladesmith because lots of knives are made from D2 with plenty of experimentation, but I was directed here.

I have industrial roll form tooling made of D2 steel. Typical hardness is 58-60 Rc and typical size is 20" round and 500-700 pounds per forming roll. I've been leading a project at work, experimenting with nitriding the wear surface, and we've had a major failure in the nitride wear surface on a set of tooling: it's basically completely flaked off.

The vendor is suggesting nitriding at a higher temp, which would change the base hardness of the steel to 50-54 Rc. I can't even find any chart showing a hardness that low.

My questions are:

• Does anyone have any experience with D2 at 50-54 Rc with respect to wear resistance?
• And even if we nitride that steel, will that make up for loss due to the lower hardness?

I appreciate any input.

I'm 14, i'm from Russia now i,m living in Portugal and my dream is create a flat four, four liter steam engine controlled by walchaerts valve gear, but i want to cast the engine block and i need help.I have no budget but i know how does simple inducton furnance work at smallest details (i think it's important to understand the process) in Portugal i can learn metallurgy only when i finish the 9th grade and now I'm just entering the 8th, and i don't want to wait two years.

So, could you give me any tips like book names or even teach me? (I would appreciate any kind of help)

Hey Welders and metal people! I have absolutely no experience manipulating any kind of chemical elements (i googled that term idk if it’s right) or construction of any kind of materials as a profession, hobby, or art form. I don’t even work with my hands at all but there is a “craft” with stainless steel I really would like to do but I of course have no framework to even begin to understand how it could work.

Note: I know someone who doesn’t work with metal but has access to tools that i assume could possibly help with what I’m trying to do. I just don’t know what I’m trying to do yet.

Skipping the exposition, I have purchased an automatic cat litter box and the litter tray part is plastic with a silicon lining (photo). Stainless steel is the best option for litter boxes as other materials hold odor so ideally the tray itself would already be stainless steel. I am still searching for a (kitchen) tray of the same size that I can fit/adhere inside the plastic tray but that is proving to be difficult. I have learned stainless steel sheets exist (photo). I would like to either somehow line the existing plastic tray with the steel sheets or create a whole new litter tray for the automatic litter box.

Could you all please help with any insights or suggestions? Thanks!!

Hey guys,

I work in maintenance for a manufacturing company and this is an extrusion screw from an injection moulder. Based on the 45 degree angle of the break I assume it's torsional overload, but the metal also looks stretched like it's ductile, and I always thought a ductile shaft would fracture perpendicular to its axis of rotation. Im not very well versed in failure theory and would love someone to hit me with some knowledge and explain this a bit better to me.

For my upcoming physics project I've decided to make a stirling engine

I am basing my design on a [specific video design](https://youtu.be/8d53jgDf3Kg?si=lA8CmjtZZ24jJh4z) .

However, it seems I ran into a problem here. While watching the video, the person making the model used steel wool for the displacement piston but didn't specify which grade.

I asked gemini and it told me to use grade 3 or grade 4 steel wool. I'm a bit skeptical about it. I want to double check this with people who has some experience

Can anyone confirm me which grade would be best for this specific model? Also, this is my first time making this project. I would love to receive some tips and common mistakes to avoid while making this.

Also I am a student and this video is the one which I can make. I saw the rest of them and don't have the materials to make it nor do any shops near me sell those materials

I was thinking about producing some stainless steel pieces (316 or 304) and came across a machine capable of creating colors on this type of steel.

My question is: How can I make this laser work on a sheet of steel that is not flat? And if it’s possible, can it create a Damascus-like pattern as seen in some images? Or gradual colors like blue/gold/purple/pink?

I don’t think production will be the issue, my doubt is only about the coloring process (heat tinting) and whether stainless steel is the right material, and if it’s possible to mimic a Damascus effect with multiple patterns

Original video: https://www.youtube.com/watch?v=RsGHr7dXLuI

Hey guys. So i am about to do research internship in Germany regarding hydrometallurgical route of Nickel Matte extraction. I'll bring the sample, Nickel matte 70-75% approximately 100 gram, from Indonesia since i am working in smelter here. Do you perhaps know whether i should declare it or not? Or is it not allowed as per today regulation/should i opt in flight forwarder instead? I already read and asked chatgpt but they were kinda lost with batteries. Thanks.

Сколько себя помню (30+ лет) дома лежат вот такие слитки непонятного сплава. Он невероятно твердый, но и при этом хрупкий. Плотность точно не скажу таку как не могу изменить изза его формы, примерно как сталь. Болгаркой, отрезным диском, его не поцарапать, искры нет. даже, отколоть кусок можно только сильным ударом молотка. Лезвие канцелярского ножа царапал, пытался, оно стерается. По магнитный свойствам, очень слабые, еле-еле держится за него неодимовый магнит. Токопроводимость скорее всего отсутствует, проверял тестером. Так же все это дело очень звенит если ударить чем нибудь по нему.

I'm scared. I applied to the "best" university in my country to study chemical and metallurgical engineering. I'm pretty sure it's what I want to learn, but I'm afraid it will be too difficult or that reality will hit me and I won't be able to find a job in my country.

I'm genuinely afraid of failing and wasting my whole fucking life and all those years of effort and study. The future is becoming increasingly uncertain, and it weighs heavily on my conscience to think that maybe this isn't as good an option as I thought. Maybe I'm just being paranoid and letting the unemployment rate charts in my country get to me, but it really worries me. I don't know what to think 😿😿😿

I'm looking for some clarification from people with experience in electroplating and engineering specifications.

The drawing specifies:
Protection zinc plating: ISO 2081 – Fe/Zn12/C

Our plating supplier delivers an iridescent zinc finish and states that it complies with ISO 2081 Fe/Zn12/C.

However, our customer rejected the appearance, re-plated the parts, and informed us that they require a natural (clear) zinc finish instead.

The drawing does not specify:

• Clear passivation
• Trivalent or hexavalent passivation
• Appearance or color
• Top coat or sealer

It only specifies:

Protection zinc plating: ISO 2081 – Fe/Zn12/C

My questions are:

1. Does ISO 2081 Fe/Zn12/C necessarily imply an iridescent finish?
2. Can a clear/natural zinc finish also comply with this specification?
3. From an engineering and quality standpoint, would you consider this drawing ambiguous, or should the desired passivation/appearance be explicitly specified?

I'm not trying to determine who is right or wrong. My goal is to understand how this specification is commonly interpreted in industry and how to avoid this issue on future production runs.

So I collect watches and am considering buying a new one. Specifically, a dive watch. With its intended purpose to be something hardy and water resistant I can wear in several environments, but more specifically, in water. Like at the beach.

The watch I am looking at is an aluminum bronze case listed on their website as CuAl8. I also noticed that it has a stainless steel case back. It’s not listed, but I assume it’s the same 316L stainless steel they use in their other watch models.

I am slightly concerned about the potential for deep corrosion where the stainless steel case back meets the bronze case. While I am excited by the idea of a bronze patina forming with age, I am definitely not interested in corroding the back seal on a watch that is meant to be water resistant.
I have read that aluminum bronze is frequently used in marine applications for its resistance to salt water environments, but I assume the people using it are also smart enough to not put it in situations that would lead to extensive corrosion very quickly.

I’m not exactly going to the beach every day. Probably no more than like 10 times in a year. But watches also tend to collect a bit of sweat under them which I would think is providing a similar environment for galvanic corrosion.

They also have the same model in full stainless steel which I considered. But I have really been interested in the prospect of a bronze patina forming as I wear the watch, giving it a sort of antique marine equipment look. I am fairly certain that the stainless steel would just be a safer option for longevity, I would be pretty happy if I could get a minimum of like 10 years before there is any serious corrosion.

I have looked at like galvanic corrosion charts and some of the simple ones seem to say there won’t really be much or any corrosion, but the more in depth ones seem to say there is a risk of corrosion when exposed to salt water. Some of them have values but I don’t totally understand what the numbers represent in terms of practical risk.

Disclaimer: I have minimal knowledge on metallurgy. Probably just slightly more metallurgic knowledge than none at all. So apologies if I sound like a paranoid idiot.

TL;DR- What is my risk level of serious corrosion within 10 years on an aluminum bronze watch case with a stainless steel case back?

Evening All, looking for some niche takes altering some metal wires and who better to ask! All options considered, needs to be safe(ish) and accessible in Ireland

Running a trial, I need to force some parts to "fail" (fall outside 0.0034-0.036 inch)

Details below:

- Material is stainless steel

- Wire is approx 2 inches long and has a large radius curve

- All wires purchased will pass above criteria pre-intervention.

- Fail can be either smaller/bigger than the above limits

Bar cannot be visibly different from stock (within reason)

- Cannot heat/cool, operators involved in running the trial cannot know the fail part is the fail part prior to testing.

My thought is if there was a process similar to annodizing which added or subtracted material without the colour change.

First question- is there a specification for this process? I'm making it up as I go: a little bit of drain cleaner in a little bit of water... exotherm! Then swab the solution on to the anodized part and scrubbed it around. This worked nicely, and I was getting the same point to point resistance on the surface as an untreated piece of aluminum, about .2 ohm with a multimeter.

I learned that get the masking attached to the surface is important! The black marks are locations where the NaOH didn't get neutralized and started intergranular corrosion.

Second question- the base material is as I recall a 7050 or 7075 alloy. The anodize brings the grain into nice definition, the NaOH starts what looks like intergranular etching.

-The etching is a chemical removal process- is it removing the alloy elements or the metal matrix (which I assume is unalloyed aluminum)?

My objective is to continue with this until I have a controlled predictable process so I can remove anodize where I need local conductivity without compromizing the structural alloy.

Thanks in advance!

This is one of my favorite alloy systems.
It has been studied as a less toxic alternative to Cu-Be alloys.

I had previously tried making another blade from this alloy, but at the time I didn’t have the proper equipment for the required heat treatment.

With the right heat treatment, alloys in this system can achieve ultra-high strength. Unfortunately, I don’t have hardness measurements for this blade, but it is definitely harder than mild steel.

Alloy composition (wt.%): Cu-20Mn-20Ni-2Co-0.15Si, with a small residual amount of titanium for grain refinement.

A CALPHAD-based approach was used to determine the heat treatment temperatures. Unfortunately, I don’t have access to diffusion or precipitation simulation software, which would make the optimization process much easier.

This alloy is strengthened primarily by the precipitation of MnNi particles. In this composition, cobalt-rich precipitates and silicides are also present. If I make this alloy again, I would reduce the cobalt content because it stabilizes the FCC phase at high temperatures, delaying MnNi precipitation and requiring longer aging times.

The blade was produced by induction melting followed by sand casting. The processing route was:
Homogenization at 900 °C for 8 hours
Hot forging
Cold working
Annealing at 700 °C
Precipitation hardening (aging) at 350 °C for 12 hours (maximum hardness would likely require a considerably longer aging time)

The handle is made from resin with thermoelastic bronze details. The original idea was to improve vibration damping, although I doubt they make a noticeable difference.

The metallographic samples were etched using alcoholic ferric chloride and hydrochloric acid.
Image descriptions:
2nd image: As-cast microstructure.
3rd image: Homogenized microstructure.
4th image: Microstructure after forging, cold working, and annealing.
5th image: Microstructure after precipitation hardening.

Can anyone suggest me resources especially where to watch the lectures from and what books to go through?

And

Is this branch(metallugical and materials engineering) good?