Application file · nine cells · two runs
Enquiries for automotive tooling rarely arrive with a grade on them. They arrive as a part: a panel, a reinforcement, a knuckle, a sheet grade with a strength class after it, a thickness, an annual volume, and a die that came off the line early.
Automotive stamping die steel and forging die steel are placed here from that starting point, on a ladder that reads the pressing side by sheet strength and the forging side by the failure that ends the die. This page sets out the ladder cell by cell, what rising sheet strength changed about cold work selection, and how a list crossing both families is answered line by line.
Fucheng supplies the die steel behind automotive pressings and forgings as one range, melted, electroslag remelted, forged, annealed and inspected inside our own works: D2, DC53, D3, D6 and O1 for blanking and forming, H13, 1.2367, H11 and 1.2714 for hot forging. Automotive stamping die steel is placed here from the part rather than from a grade name, because that is the form the enquiry takes.
The ladder · two runs
The ladder has two runs. On the pressing side the cell is read from the sheet: what it is, how strong it is, how thick, and how the last tool for that job came off the line. On the forging side it is read from the failure that ends the die: the cavity face crazing, the cavity going soft under load, or the block splitting.
Nine grades, nine cells, and every part in automotive tooling lands in one of them.
Pressing sideread from the sheet
Forging sideread from the failure
It is what the grade reaches in your hardener’s furnace, on the route you choose, and it is stated here as a property of the steel. What we ship is annealed material:
Every one of those windows is measured on the heat and printed on the certificate, and a heat that comes out above its window is annealed again and retested rather than released.
Where two cells pull against each other — a trim edge on martensitic sheet that also has to survive a long production run, a forging block that both crazes and cracks — the technical desk works it in writing on your side of the enquiry and comes back with the cell, the reason, the sections and whether they are on the shelf or scheduled. The grade mechanisms sit on the individual grade pages linked further down; this page is about which cell the part belongs in.
Six lines · one cell
Six lines carry a part from a description to a cell and a date.
| Line | What it settles |
|---|---|
| Part and die station: draw, blank, trim, pierce, forge, hot trim | Which run of the ladder, and which cell inside it |
| Sheet grade and strength class, or forging temperature and cadence | Wear against impact on the cold side, crazing against cracking on the hot side |
| Sheet thickness, or the forging section and block size | Hardening depth, movement in the quench, and which forging line the block runs down |
| Volume per year and runs between regrinds | Edge retention against edge toughness |
| Failure form of the previous tool: chipped or worn | The cell, more directly than any other line here |
| Coating: PVD, nitriding, or none | Whether the working hardness has to survive a high temper |
Sheet strength · the cell moves up
Two ways an edge stops working, one step apart, and only one of them is answered by hardness.
What buys life on the lower tread is carbide volume carried at high hardness, which is D2’s cell and part of why we keep D2 finished on the shelf. Sheet at DP 590, 780 and 980, complex phase grades and martensitic sheet changes the loading rather than the amount of it, and chipping takes over from wear.
Run the edge at full hardness and it chips sooner; drop it to buy toughness and the wear comes back.
Hardness is not the knob on this cell.
What is: the carbide structure the edge is built on, finer and less segregated so it takes the shock at the same working hardness, and a grade that can be tempered high so the working hardness is still there after a coating cycle. That is DC53’s cell, and the metallurgy behind it is on the DC53 page. It is also why D3 and D6 hold the cells where the load stays a cutting load rather than a shock load — thin sheet, slitting, shear blades — and why D2 keeps the long mild-steel runs it has always been good at.
Send the part and the sheet grade, and add one line: on the last tool for this job, was the edge chipped or worn. The reply names the cell and the reason before it names a section or a price.
That is cheap to check. Send the same enquiry to us and to two other suppliers and read the questions that come back — most replies ask for grade, size and quantity, and stop there.
The two numbers that settle it are already written down in your own shop. The tool-change log records why the last set came off: how many segments chipped, and what clearance the edge had worn to when it was pulled.
Send those two with the sheet grade and we place the work against them rather than against the grade on the last order. A distributor supplying the press shop can put the same two questions to the tool room and forward the answer intact; it is a short question with a specific answer, and it is the one that decides the cell.
Chipping and wear point at different cells. One line on the enquiry — which of the two took the last tool off the line — settles more than a page of specification does.
Forging side · three endings
Hot forging dies end three ways, and the three lead to three cells.
The cavity face crazes — a network of fine thermal cracks that prints onto every forging until the block is welded or replaced.
The cavity sinks under load, because at working temperature tempering resistance decides how long the profile holds.
Or the block cracks outright under the blow.
A line running knuckles, arms, gear blanks or CVJ parts to a takt time never lets the cavity cool down between blows, so the die sits at temperature for the whole shift and tempering resistance is doing the work rather than room-temperature hardness.
That is also why a die that behaved well on short batch work can disappoint on a volume programme in the same material: nothing about the steel changed, the duty cycle did, and the cell moves with the duty cycle.
All four ship annealed, in the HB windows above, with the choice of black forged and descaled, turned, ground or six-face milled surface. Blocks on this side are usually the heaviest sections on the list, and they are worth stating early, since the section decides which forging line the block runs down and therefore the date.
1,500 MPa class · the hardest cell
Hot-stamped boron steel parts leave the press line already quenched, in the 1,500 MPa class, and the trimming and piercing happens on material in that condition.
It is the hardest cell on the cold side of the ladder:
An edge that can be tempered high, coated, and still be at working hardness when it reaches the press. Before a set is cut, a quench coupon from the same heat runs your own hardening route and reports measured hardness and dimensional change, so the tool room knows what that block does in that furnace before the machining hours go in.
Named on the order · run on your heat
Three items are available on any order in this range, named on the order and run on your heat.
A sample from the same heat as your blocks, taken through the hardening and tempering route you specify, with the measured hardness and the dimensional change reported back. It is available on every annealed-delivery grade on this page, and for automotive work it does two jobs: it confirms the cell before a set of inserts is machined, and it puts a number on movement in advance rather than after the quench.
Covers the hot work grades, with specimen orientation as you specify it.
Run to ASTM E45, DIN 50602 or ISO 4967, whichever your customer’s tool room works to.
Mixed list · line by line
An automotive list crosses both families by nature.
A press shop list carries D2 alongside DC53 or D6; a forge shop list carries H13 alongside 1.2367 or 1.2714; a tier supplier running both puts all of it on one enquiry. Two of the nine grades sit inside the roughly 8,000 tonnes we hold finished — H13 and D2 — and the other seven run to production.
7 – 10 days
Stocked sections are confirmed against the 7 to 10 day window with the section and quantity beside them.
25 – 35 days
Production lines carry 25 to 35 days each, covering melting, forging, annealing, finishing and inspection. Every line gets its own date, and no single date is quoted over the whole list.
Send a real list with H13 or D2 on it plus one of the other seven and read the reply. A supplier who buys his steel in cannot split a list line by line, because he does not know which of those lines his own source is holding this week; what comes back is one date over everything, or a range wide enough to cover both cases.
A first order can run as a trial before a programme leans on the supply, on the same terms as a repeat. A stocked size drawn down by a large set is replaced out of our own melt shop rather than bought in, so the same list answers at the same speed next quarter.
Section first · then the date
Black forged material carries 3 to 6 mm of allowance per side depending on section. Cut to length holds ±2 mm, ground thickness holds ±0.05 mm, and milled surfaces hold flatness within 0.1 mm per metre.
The works behind the nine cells
Every batch · EN 10204 3.1
Every batch of automotive stamping die steel ships with an EN 10204 3.1 material test certificate, signed by a quality department that reports to the general manager rather than to production.
Eight inspection steps stand behind it, from appearance and dimensions through chemistry, hardness, ultrasonic and magnetic particle testing to metallography and carbide rating.
Material that misses a window is sorted out and not shipped, the heat behind it re-inspected and the shortfall made up off our own line rather than passed on as a concession. Records stay against the heat number for ten years, the horizon a die programme actually runs on.
Already decided · each costs elsewhere
Four choices arrive already made on automotive enquiries, and each one costs at a different point.
It chips inside the first weeks, long before the first scheduled regrind, and the argument about the cause lands on whoever supplied the steel. That work belongs in the DC53 cell, and the two questions above catch it at the enquiry.
Cell: DC53
Section decides how deep the hardness goes and how much the block moves: heavier sections harden shallower and move more, and the machining hours are already in the block by then. Send the section and the finished tool and the cell is set against them; D3 and D6 show where those grades do belong.
Cell: set against the section
Crazing and cracking are different cells, and the wrong one buys a property the tool was never short of.
Cell: read the failure, not the grade
The coating cycle takes the working hardness with it.
Cell: needs a high temper
Programmes · not one-off orders
We supply distributors, stockholders and wholesalers, and the press shops and forge shops they serve remain their accounts.
Automotive tooling moves as programmes rather than as one-off orders: a die set goes in once and is then fed with replacement inserts, blades and punches for as long as the model runs, which is why half a die list is worth holding and the rest is worth scheduling.
The full enquiry checklist sits on the contact page; the works, the people and the visit policy are on the about us page.
Detail lives · one level down
Tooling for moulded interior and lighting parts runs on a different ladder.
The cell · a date per line
Two lines start it: the part with its sheet grade and thickness, and how the last tool for that job came off — chipped or worn.
Back comes the ladder cell with the reason behind it, the sections, and a date against every line. Working-day replies run inside 24 hours. Name your hardening route as well and a quench coupon from the same heat goes on the order, so the movement is measured in your own furnace ahead of the first insert.
Working days, Monday to Friday 09:00–18:00 GMT+8. We supply distributors, stockholders, wholesalers and buyers procuring at scale.
Or write directly: wonderful@fcstoolsteel.com
WhatsApp: +86-18972782802