{"id":3407,"date":"2026-10-09T01:53:36","date_gmt":"2026-10-08T17:53:36","guid":{"rendered":"http:\/\/www.jendelarakyat.com\/blog\/?p=3407"},"modified":"2026-10-09T01:53:36","modified_gmt":"2026-10-08T17:53:36","slug":"what-are-the-requirements-for-the-electrical-performance-of-micro-motor-stamping-parts-4e31-09e31d","status":"publish","type":"post","link":"http:\/\/www.jendelarakyat.com\/blog\/2026\/10\/09\/what-are-the-requirements-for-the-electrical-performance-of-micro-motor-stamping-parts-4e31-09e31d\/","title":{"rendered":"What are the requirements for the electrical performance of micro motor stamping parts?"},"content":{"rendered":"

If you\u2019ve ever held a quiet, precise electric toothbrush, a buzz-free drone motor, or a tiny pump that delivers insulin accurately, you\u2019ve held a micro motor. At my stamping parts shop\u2014where we\u2019ve made components for these exact applications for over 12 years\u2014every part that goes into those motors starts as a thin sheet of metal, pressed into shape with dies machined to tolerances so tight we measure them in micrometers. Early on, I learned a hard lesson: a part that looks right to the naked eye can ruin a motor\u2019s performance if its electrical properties are off. That\u2019s why, after thousands of runs and hundreds of customer audits, I can tell you that the electrical performance requirements for micro motor stamping parts aren\u2019t just \u201cnice to have\u201d\u2014they\u2019re the foundation of the motor\u2019s efficiency, lifespan, and reliability. Let\u2019s break down what those requirements actually mean, why they matter, and how we (as a supplier) deliver on them. Micro Motor Stamping Parts<\/a><\/p>\n

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First, let\u2019s define what we\u2019re talking about. Micro motor stamping parts are usually thin laminations of electrical steel (silicon steel) or occasionally non-ferrous metals like copper or aluminum, stamped into circular cores, stator teeth, rotor slots, or end plates that make up the motor\u2019s magnetic circuit. Their primary electrical job is to carry and guide the electromagnetic flux that powers the motor. If that flux leaks, causes unwanted currents, or encounters too much resistance, the motor loses power, overheats, or burns out early. That\u2019s why the first and most critical requirement is low core loss.<\/p>\n

Core loss, also called iron loss, comes in two parts: hysteresis loss and eddy current loss. Hysteresis loss happens when the magnetic domains in the steel flip back and forth as the motor\u2019s current cycles. If the material isn\u2019t properly processed, those domains resist flipping, wasting energy as heat. Eddy current loss is even more insidious: when magnetic flux passes through a conductive metal, it induces small, circular currents (eddies) in the lamination itself. In thick metal, these eddies are huge, but even in thin laminations, if the lamination is too thick or the steel has high electrical conductivity, those eddies drain power. For micro motors\u2014where size is everything and every watt counts\u2014core loss has to be as low as possible. Our shop works with electrical steel grades specifically formulated for low core loss, and we insist on laminations no thicker than 0.2mm, often 0.1mm, for high-speed micro motors. We test every batch of stamped cores with an Epstein frame tester, which measures core loss at standard frequencies (common are 50Hz, 60Hz, and up to 1kHz for micro motors) to make sure they fall within 2-3 W\/kg at 1.5T flux density\u2014numbers our customers in the drone and medical device industries won\u2019t accept above.<\/p>\n

Next up is electrical resistivity, or how well the stamping part resists the flow of unintended current. Wait, isn\u2019t electrical steel supposed to conduct magnetic flux? Yes, but we only want it to conduct that magnetic flux\u2014not stray currents. For stator and rotor cores, high resistivity is key to minimizing eddy currents. Electrical steel is doped with silicon to boost resistivity: adding 3-5% silicon increases resistivity by about 50% compared to plain carbon steel, which cuts eddy loss dramatically. But here\u2019s the catch: too much silicon makes the steel brittle, impossible to stamp into the tiny, precise shapes micro motors need (some stator teeth are less than 1mm wide). So we source steel with the optimal silicon content, and our stamping processes are calibrated to avoid introducing microcracks that would lower resistivity. For non-ferrous stampings, like copper rotor bars in permanent magnet micro motors, resistivity is a balance: we need low resistivity to carry the current that generates torque, but not so low that adjacent parts create short circuits. For example, copper end rings stamped for small BLDC motors have to hold a resistivity of less than 1.7 x 10^-8 \u03a9\u00b7m at 20\u00b0C\u2014something we verify with a 4-point probe tester on every production run. The last thing a customer wants is a micro motor that can\u2019t reach full torque because its rotor bars are too resistive.<\/p>\n

Dielectric strength and insulation integrity are the next big requirements, and they\u2019re especially important when stamping parts for multi-phase motors or motors that run on low voltage (like those in wearables or hearing aids). Wait\u2014why would a stamping part need dielectric strength? Because the laminations in a stator core aren\u2019t just stacked together; each lamination has a thin insulating coating (usually a ceramic or organic layer) that separates it from the next one. If that coating is scratched during stamping, or too thin to begin with, adjacent laminations can conduct electricity between each other, creating a short circuit in the core that ruins the motor. Dielectric strength measures how much voltage the insulation can withstand before breaking down. For micro motor laminations, that\u2019s usually at least 1000V per 0.01mm of insulation coating. We have a separate quality team that checks every coil of incoming steel for coating thickness and adhesion with a magnetic thickness gauge and a scratch test before we even stamp it. Last year, a customer from a medical pump manufacturer caught a batch of parts with uneven coating in their audit, and we caught it before delivery\u2014saving them a potential product recall. That\u2019s the kind of standard we live by.<\/p>\n

Then there\u2019s contact resistance, which is about how well two stamping parts fit together when they\u2019re assembled into the motor. Think of a stator stack: you have 50-100 stamped laminations stacked and bonded or pressed together. If the contact between each lamination has high resistance, that creates an additional path for eddy currents, increasing heat and lowering efficiency. For that reason, we specify that contact resistance between stamped lamination surfaces should be less than 5 m\u03a9 per square centimeter under normal assembly pressure. We achieve this by making sure the stamping edges are smooth (no burrs taller than 0.005mm, measured with a laser comparator) and the stack is compressed to a consistent height, with a pressure of about 10-20 MPa depending on the motor size. For stamped end plates or bearing housings that interface with other motor parts, contact resistance matters too\u2014high contact resistance at the bearing can cause electrical arcing, which eats away at the bearing surface and causes the motor to seize prematurely. We test contact resistance on every pilot run with a four-point probe setup that mimics assembly conditions, so our customers never have to deal with that issue.<\/p>\n

Wait a second\u2014what about when we make non-ferrous stampings, like copper terminals for micro motors? Their electrical requirements are a little different. For terminals, we need consistent conductivity to ensure power is delivered from the motor\u2019s leads to the windings without loss, and also corrosion resistance, because a corroded terminal has high resistance and can cause intermittent power loss. We use electrolytic copper for most terminals, which has conductivity of at least 58 MS\/m, and we tin-plate all exposed terminal surfaces to prevent corrosion. For small signal motors used in cameras or robotics, terminals also have to meet low contact resistance standards when mated to connectors\u2014usually less than 20 m\u03a9 per connection. We\u2019ve had customers who switched from cheaper, unplated terminals and saw their motor failure rates jump by 15% over six months; since we started offering tin-plated terminals, their failure rates dropped to near zero. That\u2019s a real example of how a seemingly small stamping detail affects electrical performance.<\/p>\n

Now, let\u2019s talk about the edge quality of stamped parts, which is often overlooked but critical for electrical performance. When you stamp a part, the edge isn\u2019t perfectly smooth\u2014it has a small burr, a rollover, and a fracture zone. For micro motor parts, a burr as small as 0.01mm can pierce the insulation coating between laminations, create a short circuit, or cause excessive wear on the motor\u2019s brushes (if it\u2019s a brushed motor). We invest in high-precision progressive stamping dies with carbide punches and dies, so we can hold burr heights to less than 0.003mm\u2014about a third the thickness of a human hair. We also deburr every part in a vibratory tumbler with ceramic media, a process we calibrated over years to remove burrs without scratching the surface or altering the part\u2019s dimensions. Early on, we thought deburring was a waste of time, until a major drone manufacturer rejected a batch of parts because their motors were shorting during high-altitude tests. Tracing the issue, we found that the burrs from our older dies were piercing the insulation in the stator cores at high vibration. That\u2019s when we realized edge quality isn\u2019t just a cosmetic thing\u2014it\u2019s core to electrical performance.<\/p>\n

Temperature stability is another requirement, because micro motors can run at high speeds (up to 100,000 RPM for some applications) and get hot. The electrical properties of stamping parts change with temperature: resistivity increases as temperature goes up, which can lower efficiency, and core loss also rises. For this reason, we have to make sure that the stamping parts maintain their electrical specifications across the operating temperature range of the motor, usually from -40\u00b0C to 125\u00b0C for industrial and automotive micro motors. We test resistivity at both low and high temperatures in a temperature chamber, so we can guarantee that our parts won\u2019t cause a motor to overheat or lose torque when it\u2019s used in extreme conditions\u2014like a drone flying in the Arctic, or a medical pump operating inside a patient\u2019s body (where temperatures are constant, but small deviations matter).<\/p>\n

I often get asked by new customers: \u201cCan you just stamp this shape, and we\u2019ll handle the electrical stuff?\u201d The answer is no. Because every choice we make during stamping\u2014from the grade of steel we use, to the die material, to the deburring process\u2014affects the final electrical performance. Last year, we had a startup that was making a new line of micro motors for wearable fitness trackers. They tried stamping their own laminations with cheap steel and old dies, and their motors had a 20% higher core loss than their target, so the trackers\u2019 batteries died twice as fast. They came to us, and we switched them to a low-loss electrical steel, upgraded their dies, calibrated the lamination thickness, and within a month their core loss was down to the required level, and battery life matched their design specs. That\u2019s the kind of problem-solving we do, because we know that if our stamping parts don\u2019t meet electrical requirements, the whole motor fails.<\/p>\n

So to recap, the key electrical performance requirements for micro motor stamping parts are: low core loss (tested at operating frequencies and flux densities), high electrical resistivity (for ferrous cores, balanced with workability), sufficient dielectric strength and insulation integrity (to prevent short circuits), low contact resistance between mating parts, minimal edge burrs (to avoid coating damage and arcing), consistent conductivity (for non-ferrous parts like terminals), and stable electrical properties across operating temperatures.<\/p>\n

<\/p>\n

At the end of the day, as a micro motor stamping parts supplier, our job isn\u2019t just to cut metal into shapes. It\u2019s to deliver parts that work so well, you never even think about them\u2014you just get a motor that runs quiet, lasts for years, and delivers exactly the performance it\u2019s supposed to. If you\u2019re designing a new micro motor, or having issues with stamping part performance, I\u2019d be happy to walk through your requirements, share our test data, and work with you to find the right solution. Let\u2019s connect and talk about how we can help your project succeed.<\/p>\n

Stamping Small Parts<\/a> References<\/p>\n

    \n
  1. Bosch, R. (2018). Electrical Steels for Rotating Machines: Materials, Design, and Applications. Bosch GmbH.<\/li>\n
  2. Miller, T.J.E. (2014). Electronic Control of Switched Reluctance Motors. Elsevier.<\/li>\n
  3. International Electrotechnical Commission (IEC) 60404-8-7: Magnetic Materials \u2013 Part 8-7: Specifications for Individual Materials \u2013 Electrical Steels for Rotating Machines. IEC.<\/li>\n
  4. NEMA Standard MI-25: Methods for Measurement of Magnetic Properties of Electrical Steel Sheet and Strip. National Electrical Manufacturers Association.<\/li>\n<\/ol>\n
    \n

    Yuyao Aozhou Metal Products Co., Ltd.<\/a>
    We are one of the most experienced micro motor stamping parts manufacturers and suppliers in China. With a professional production team, we are able to meet the needs of the majority of our customers. Please rest assured to buy customized micro motor stamping parts made in China here from our factory.
    Address: No.6, Nanbailonggang, Wuma Industrial Zone, Lubu Town, Yuyao City
    E-mail: xqr-2316@163.com
    WebSite:     https:\/\/www.cnaozhou.com\/<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

    If you\u2019ve ever held a quiet, precise electric toothbrush, a buzz-free drone motor, or a tiny … What are the requirements for the electrical performance of micro motor stamping parts?<\/span>Read more<\/a><\/p>\n","protected":false},"author":40,"featured_media":3407,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[3370],"class_list":["post-3407","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-industry","tag-micro-motor-stamping-parts-4f3a-0a229e"],"_links":{"self":[{"href":"http:\/\/www.jendelarakyat.com\/blog\/wp-json\/wp\/v2\/posts\/3407","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.jendelarakyat.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.jendelarakyat.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.jendelarakyat.com\/blog\/wp-json\/wp\/v2\/users\/40"}],"replies":[{"embeddable":true,"href":"http:\/\/www.jendelarakyat.com\/blog\/wp-json\/wp\/v2\/comments?post=3407"}],"version-history":[{"count":0,"href":"http:\/\/www.jendelarakyat.com\/blog\/wp-json\/wp\/v2\/posts\/3407\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.jendelarakyat.com\/blog\/wp-json\/wp\/v2\/posts\/3407"}],"wp:attachment":[{"href":"http:\/\/www.jendelarakyat.com\/blog\/wp-json\/wp\/v2\/media?parent=3407"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.jendelarakyat.com\/blog\/wp-json\/wp\/v2\/categories?post=3407"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.jendelarakyat.com\/blog\/wp-json\/wp\/v2\/tags?post=3407"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}