In late 2006, just a few weeks after Vale, the Brazilian mining group, bought Inco, the Canadian nickel miner, for $17.6bn, a meeting between executives of the two companies hinted at a potentially difficult future.

According to a former Inco exec-utive, the session ended abruptly with one of the Brazilians losing his temper. "How come, if you're so smart, you didn't take us over?" he snap-ped.

Worse was to follow. A succession of senior Canadian managers as well as key engineers and operating staff walked out the door. Another former Inco executive says that of 29 colleagues who took part in a senior management strategy session in early 2007, only six remain.

The tensions came to a head last July when more than 3,100 members of the United Steelworkers union went on strike at Inco's flagship operations in Sudbury, Ontario, and a refinery near Niagara Falls.

They are still off the job. Exploratory talks aimed at a settlement broke down earlier this week with the union rejecting a new Vale offer on the grounds that it fell "far short of the . . . membership's expectations".

The acquisition of the Canadian company, which the new owner renamed Vale Inco, turned Vale, whose core business is iron ore, into the world's second-biggest mining group by market capitalisation.

The question now is whether the upheaval at the Canadian operation could be a taste of things to come in other parts of the world as Brazilian companies increasingly flex their muscles overseas. Groups such as Gerdau, a steelmaker, and Marcopolo, a busmaker, were busy buying foreign assets before the global crisis struck and, if the recovery continues, more are expected to follow. Vale's experience reveals the kind of challenges they may face.

"We're a culture of 'why?'" says a former Inco executive, referring to the constant exchange of ideas and decentralised decision-making that was encouraged by the former Canadian management. On the other hand, he says, "the Brazilians were: 'I told you to do this. Now do it.'" (Former Inco executives who spoke to the Financial Times asked not to be identified.)

At the same time, the Brazilians encountered more resistance than they expected.

Francisco Alves, editor of Brasil Mineral magazine, which covers the mining sector, argues that Canadian companies were more accustomed to taking over Latin American mining operations than the other way round. "Brazil was still seen as an underdeveloped, colonial country, so accepting the takeover didn't come naturally," he says.

Even without the north-south divide, however, Vale might have had a hard time putting its stamp on its new acquisition.

Iron ore and nickel have little in common apart from both being widely used metals. The former is a basic commodity, mined in huge quantities in a relatively simple operation and typically sold under fixed-price contracts. Nickel, a key ingredient in stainless steel, is a more complex business, involving underground mining, day-to-day price movements and costly research into new applications.

Hinting at the disdain that the Canadians felt towards their new bosses, one of the former Inco employees says that "to run an iron ore business is almost like a high school diploma. Nickel is a PhD."

Even so, Inco, founded almost a century ago, had a reputation as a sleepy company operating well below its potential. According to David Robinson, a professor of economics at Laurentian University in Sudbury: "Management did a poor job of getting the most out of the workers."

The company and the union, he continues, "established a modus operandi in the past where neither side played too rough. That's the Canadian way."