Sumitomo AC405K: the maker lists AC4010K as its successor
Sumitomo Electric puts Sumitomo AC4010K against AC405K in its own catalogue material. We publish the pair only because the maker printed it; the source and page are below.
What the maker's document shows
AC405K → AC4010K · K / cast iron turning (CVD)
The table has a "Grade" column and an "Old Grades" column. AC4010K is in the Grade column; AC405K is in its Old Grades column.
Source: Sumitomo Electric, General catalogue 2025–2026, coated carbide grade table, printed page A27 (PDF page 27). Open the maker's PDF at that page →
Text line as extracted from the PDF (table columns run together)
AC4010K 91.1 2.5 ABSOTECH 20 · New thick coating realises stable long tool life even with ultra- AC405K
What this does and does not mean
It means the maker positions AC4010K as the newer grade for the work AC405K was used for. It does not say AC405K is discontinued, and it does not say every insert shape and chipbreaker you buy in AC405K exists in AC4010K.
Before you switch:
- Check that your exact insert designation and chipbreaker are offered in AC4010K in the maker's current catalogue.
- Start from the maker's recommended cutting speed for AC4010K, not the numbers you ran with AC405K.
- Run both grades until the edge is worn out on the same part and compare parts per edge. One part is not a result.
Other Sumitomo successor pairs
AC230 → ACP100 · AC304 → AC630M · AC420K → AC4125K · AC610M → AC6020M · AC700G → AC420K · AC8015P → AC8115P · AC810P → AC8015P · AC830P → AC8035P · ACP100 → ACP2000
Tell the advisor your insert, material and operation. It answers brand-neutral, including options from other makers. To check a whole tool list for older grades, use the free coverage check.